adj · noun · 14 senses · updated from the 2026-07-25 local source snapshot
Definitions and examples are grouped by meaning. Pronunciation, history, word forms, translations, descendants, synonyms, antonyms, derived terms, and related words appear whenever the source provides them.
Sound
Pronunciation
Each Play button uses your device's default local English voice, or a natural local fallback. The selected voice name appears after playback. This is synthesized speech, not a source recording.
/ɪˈfɛktɪv/weak vowel distinction
US:Recorded audio is listed in the source snapshot.
/əˈfɛktɪv/weak vowel merger
Australian:/əˈfektɪv/
homophone: affective (weak vowel merger)
rhymes with -ɛktɪv
CMU ARPABET:IH0 F EH1 K T IH0 V
Digits mark lexical stress: 1 primary, 2 secondary, 0 unstressed.
CMU ARPABET 2:IY1 F EH0 K T IH0 V
Digits mark lexical stress: 1 primary, 2 secondary, 0 unstressed.
1
adj
Meaning 1
Having the power to produce a required effect or effects.
Definition source: English Wiktionary via Wiktextract
Examples
The pill is an effective method of birth control.
Meaning relationships
Synonyms: efficacious
Antonyms: none provided
2
adj
Meaning 2
Producing a decided or decisive effect.
Definition source: English Wiktionary via Wiktextract
Examples
The president delivered an effective speech!
Meaning relationships
Synonyms: telling
Antonyms: none provided
3
adj
Meaning 3
Efficient, serviceable, or operative, available for useful work.
Definition source: English Wiktionary via Wiktextract
Examples
How long does it take to make a bunch of civilians an effective military force?
My effective income after taxes and child support is $500 a month.
The effective radiated power is determined by multiplying the transmitter power output with the antenna gain.
The effective voltage of an alternating current is 0.7 times its peak voltage.
Meaning relationships
Synonyms: none provided
Antonyms: nominal
4
adj
Meaning 4
Actually in effect.
Definition source: English Wiktionary via Wiktextract
Examples
effective immediately
The curfew is effective at midnight.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
5
adj
Meaning 5
Having no negative coefficients.
Definition source: English Wiktionary via Wiktextract
Topics: geometry, mathematics, sciences
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
6
adj
Meaning 6
Such that no group element acts trivially.
Definition source: English Wiktionary via Wiktextract
Topics: algebra, mathematics, sciences
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
7
adj
Meaning 7
approximate; Not describing the fundamental dynamic changes in some system as they happen.
Definition source: English Wiktionary via Wiktextract
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
8
noun
Meaning 8
a soldier fit for duty
Definition source: English Wiktionary via Wiktextract
Topics: government, military, politics, war
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
9
adjective
Meaning 9
producing or capable of producing an intended result or having a striking effect-LewisMumford
Definition source: Princeton WordNet 3.0
Examples
an air-cooled motor was more effective than a witch's broomstick for rapid long-distance transportation
effective teaching methods
effective steps toward peace
made an effective entrance
his complaint proved to be effectual in bringing action
an efficacious law
Meaning relationships
Synonyms: effectual, efficacious
Antonyms: ineffective
10
adjective satellite
Meaning 10
existing in fact; not theoretical; real
Definition source: Princeton WordNet 3.0
Examples
a decline in the effective demand
confused increased equipment and expenditure with the quantity of effective work done
Meaning relationships
Synonyms: none provided
Antonyms: none provided
11
adjective satellite
Meaning 11
able to accomplish a purpose; functioning effectively-G.B.Shaw
Definition source: Princeton WordNet 3.0
Examples
people who will do nothing unless they get something out of it for themselves are often highly effective persons...
effective personnel
an efficient secretary
the efficient cause of the revolution
Meaning relationships
Synonyms: efficient
Antonyms: none provided
12
adjective satellite
Meaning 12
exerting force or influence
Definition source: Princeton WordNet 3.0
Examples
the law is effective immediately
a warranty good for two years
the law is already in effect (or in force)
Meaning relationships
Synonyms: good, in effect(p), in force(p)
Antonyms: none provided
13
adjective satellite
Meaning 13
works well as a means or remedy
Definition source: Princeton WordNet 3.0
Examples
an effective reprimand
a lotion that is effective in cases of prickly heat
Meaning relationships
Synonyms: none provided
Antonyms: none provided
14
adjective satellite
Meaning 14
ready for service
Definition source: Princeton WordNet 3.0
Examples
the fort was held by about 100 effective soldiers
Meaning relationships
Synonyms: none provided
Antonyms: none provided
History
Etymology
Etymology tree Proto-Indo-European *h1éǵh Proto-Indo-European *-s Proto-Indo-European *h1éǵhs Proto-Italic *eks Latin ex Latin ef- Proto-Indo-European *dheh1- Proto-Indo-European *dheh1k- Proto-Indo-European *-yéti Proto-Indo-European *dhh1kyéti Proto-Italic *θakjō Proto-Italic *fakjō Latin faciō Latin efficiō Proto-Indo-European *-wós Proto-Indo-European *-iHwósder. Latin -īvus Latin effectīvusbor. French effectifder. English effective From French effectif, from Latin effectīvus (“productive; effective”), from efficiō (“to make; to bring about”), equivalent to effect + -ive.
Across languages
Translations
149 source translations are retained for this English entry.
Arabic:
فَعَّال
(faʕʕāl)
— having the power to produce a required effect or effects
Belarusian:
эфекты́ўны
(efjektýwny)
— having the power to produce a required effect or effects
Bulgarian:
ефекти́вен
(efektíven)
— having the power to produce a required effect or effects
Catalan:
eficaç
— having the power to produce a required effect or effects
Danish:
virksom
— having the power to produce a required effect or effects
Danish:
effektiv
— having the power to produce a required effect or effects
Dutch:
efficiënt
— having the power to produce a required effect or effects
Dutch:
werkzaam
— having the power to produce a required effect or effects
Dutch:
effectief
— having the power to produce a required effect or effects
Egyptian:
mn:n-x*U22:Y1
(mnḫ)
— having the power to produce a required effect or effects
Esperanto:
efika
— having the power to produce a required effect or effects
Finnish:
tehokas
— having the power to produce a required effect or effects
Finnish:
vaikuttava
— having the power to produce a required effect or effects
Finnish:
tehoava
— having the power to produce a required effect or effects
Finnish:
toimiva
— having the power to produce a required effect or effects
Finnish:
tuloksia tuottava
— having the power to produce a required effect or effects
French:
efficace
— having the power to produce a required effect or effects
German:
wirksam
— having the power to produce a required effect or effects
German:
effektiv
— having the power to produce a required effect or effects
German:
wirkungsvoll
— having the power to produce a required effect or effects
Gothic:
𐍅𐌰𐌿𐍂𐍃𐍄𐍅𐌴𐌹𐌲𐍃
(waurstweigs)
— having the power to produce a required effect or effects
Ancient Greek:
πρακτικός
(praktikós)
— having the power to produce a required effect or effects
Ancient Greek:
δραστήριος
(drastḗrios)
— having the power to produce a required effect or effects
Ancient Greek:
ἐνεργής
(energḗs)
— having the power to produce a required effect or effects
Ancient Greek:
ἐνεργητικός
(energētikós)
— having the power to produce a required effect or effects
Hebrew:
יָעִיל
(ya'íl)
— having the power to produce a required effect or effects
Hebrew:
אפקטיבי
(efektívi)
— having the power to produce a required effect or effects
Hungarian:
hatásos
— having the power to produce a required effect or effects
Hungarian:
hatékony
— having the power to produce a required effect or effects
Hungarian:
hathatós
— having the power to produce a required effect or effects
Hungarian:
eredményes
— having the power to produce a required effect or effects
Hungarian:
célravezető
— having the power to produce a required effect or effects
Indonesian:
efektif
— having the power to produce a required effect or effects
Irish:
éifeachtach
— having the power to produce a required effect or effects
Italian:
efficace
— having the power to produce a required effect or effects
Kazakh:
тиімді
(tiımdı)
— having the power to produce a required effect or effects
Kazakh:
нәтижелі
(nätijelı)
— having the power to produce a required effect or effects
Latin:
efficax
— having the power to produce a required effect or effects
Latvian:
iedarbīgs
— having the power to produce a required effect or effects
Malay:
berkesan
— having the power to produce a required effect or effects
Māori:
pekepakihiwi
— having the power to produce a required effect or effects
Norwegian:
virkningsfull
— having the power to produce a required effect or effects
Polish:
efektywny
— having the power to produce a required effect or effects
Polish:
skuteczny
— having the power to produce a required effect or effects
Portuguese:
eficaz
— having the power to produce a required effect or effects
Portuguese:
efetivo
— having the power to produce a required effect or effects
Romanian:
eficace
— having the power to produce a required effect or effects
Russian:
эффекти́вный
(effektívnyj)
— having the power to produce a required effect or effects
Sanskrit:
साधन
(sādhana)
— having the power to produce a required effect or effects
Scottish Gaelic:
èifeachdach
— having the power to produce a required effect or effects
Serbo-Croatian:
учинко̀вит
— having the power to produce a required effect or effects
Serbo-Croatian:
е̏фектӣван
— having the power to produce a required effect or effects
Serbo-Croatian:
učinkòvit
— having the power to produce a required effect or effects
Serbo-Croatian:
ȅfektīvan
— having the power to produce a required effect or effects
Slovak:
účinný
— having the power to produce a required effect or effects
Lower Sorbian:
statkowny
— having the power to produce a required effect or effects
Lower Sorbian:
efektiwny
— having the power to produce a required effect or effects
Spanish:
efectivo
— having the power to produce a required effect or effects
Spanish:
eficaz
— having the power to produce a required effect or effects
Spanish:
presentáneo
— having the power to produce a required effect or effects
Swedish:
effektiv
— having the power to produce a required effect or effects
Swedish:
verksam
— having the power to produce a required effect or effects
Swedish:
verkningsfull
— having the power to produce a required effect or effects
Tagalog:
mabisa
— having the power to produce a required effect or effects
Tagalog:
epektibo
— having the power to produce a required effect or effects
Tagalog:
epektib
— having the power to produce a required effect or effects
Thai:
มีประสิทธิภาพ
— having the power to produce a required effect or effects
Thai:
มีประสิทธิผล
— having the power to produce a required effect or effects
Turkish:
efektif
— having the power to produce a required effect or effects
Ukrainian:
ефекти́вний
(efektývnyj)
— having the power to produce a required effect or effects
Welsh:
effeithiol
— having the power to produce a required effect or effects
Yiddish:
עפֿעקטיוו
(efektiv)
— having the power to produce a required effect or effects
Bulgarian:
резултатен
(rezultaten)
— producing a decided or decisive effect
Catalan:
eficaç
— producing a decided or decisive effect
Danish:
effektiv
— producing a decided or decisive effect
Danish:
virksom
— producing a decided or decisive effect
Dutch:
effectief
— producing a decided or decisive effect
Finnish:
vaikuttava
— producing a decided or decisive effect
French:
efficace
— producing a decided or decisive effect
French:
décisif
— producing a decided or decisive effect
German:
wirksam
— producing a decided or decisive effect
Greek:
αποτελεσματικός
(apotelesmatikós)
— producing a decided or decisive effect
Ancient Greek:
ἀνύσιμος
(anúsimos)
— producing a decided or decisive effect
Ancient Greek:
ἀνυστικός
(anustikós)
— producing a decided or decisive effect
Hungarian:
hatásos
— producing a decided or decisive effect
Hungarian:
megfelelő
— producing a decided or decisive effect
Hungarian:
találó
— producing a decided or decisive effect
Indonesian:
efektif
— producing a decided or decisive effect
Latin:
efficax
— producing a decided or decisive effect
Latvian:
iedarbīgs
— producing a decided or decisive effect
Māori:
pekepakihiwi
— producing a decided or decisive effect
Norwegian:
virkningsfull
— producing a decided or decisive effect
Portuguese:
eficaz
— producing a decided or decisive effect
Romanian:
de efect
— producing a decided or decisive effect
Russian:
результати́вный
(rezulʹtatívnyj)
— producing a decided or decisive effect
Scottish Gaelic:
èifeachdach
— producing a decided or decisive effect
Swedish:
effektiv
— producing a decided or decisive effect
Ukrainian:
результати́вний
(rezulʹtatývnyj)
— producing a decided or decisive effect
Yiddish:
עפֿעקטיוו
(efektiv)
— producing a decided or decisive effect
Bulgarian:
ефикасен
(efikasen)
— efficient, serviceable, or operative
Catalan:
eficaç
— efficient, serviceable, or operative
Finnish:
vaikuttava
— efficient, serviceable, or operative
Finnish:
tehollinen
— efficient, serviceable, or operative
Finnish:
tosiasiallinen
— efficient, serviceable, or operative
Finnish:
käytettävissä oleva
— efficient, serviceable, or operative
French:
efficace
— efficient, serviceable, or operative
German:
effektiv
— efficient, serviceable, or operative
German:
wirkungsvoll
— efficient, serviceable, or operative
Hungarian:
effektív
— efficient, serviceable, or operative
Hungarian:
tényleges
— efficient, serviceable, or operative
Hungarian:
valóságos
— efficient, serviceable, or operative
Hungarian:
hasznos
— efficient, serviceable, or operative
Hungarian:
hasznavehető
— efficient, serviceable, or operative
Hungarian:
használható
— efficient, serviceable, or operative
Hungarian:
működő
— efficient, serviceable, or operative
Italian:
efficiente
— efficient, serviceable, or operative
Norwegian:
effektiv
— efficient, serviceable, or operative
Portuguese:
eficaz
— efficient, serviceable, or operative
Romanian:
net
— efficient, serviceable, or operative
Russian:
эффекти́вный
(effektívnyj)
— efficient, serviceable, or operative
Russian:
де́йственный
(déjstvennyj)
— efficient, serviceable, or operative
Scottish Gaelic:
èifeachdach
— efficient, serviceable, or operative
Slovak:
účinný
— efficient, serviceable, or operative
Slovak:
skutočný
— efficient, serviceable, or operative
Swedish:
verksam
— efficient, serviceable, or operative
Swedish:
funktionell
— efficient, serviceable, or operative
Swedish:
fungerande
— efficient, serviceable, or operative
Tagalog:
mapakipakinabang
— efficient, serviceable, or operative
Ottoman Turkish:
دركار
(derkâr)
— efficient, serviceable, or operative
Yiddish:
עפֿעקטיוו
(efektiv)
— efficient, serviceable, or operative
Bulgarian:
действи́телен
(dejstvítelen)
— actually in effect
Catalan:
efectiu
— actually in effect
Dutch:
effectief
— actually in effect
Finnish:
voimassa
— actually in effect
Finnish:
voimassa oleva
— actually in effect
French:
en vigueur
— actually in effect
German:
wirksam
— actually in effect
German:
in Kraft
— actually in effect
Hungarian:
hatályos
— actually in effect
Hungarian:
érvényes
— actually in effect
Hungarian:
hatályban lévő
— actually in effect
Hungarian:
érvényben lévő
— actually in effect
Indonesian:
efektif
— actually in effect
Norwegian:
virksom
— actually in effect
Polish:
efektywny
— actually in effect
Portuguese:
efetivo
— actually in effect
Russian:
де́йствующий
(déjstvujuščij)
— actually in effect
Russian:
действи́тельный
(dejstvítelʹnyj)
— actually in effect
