noun · 5 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
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UK:/diːsɛləˈɹeɪʃən/
Southern-England:Recorded audio is listed in the source snapshot.
US:/dɪˌsɛləˈɹeɪʃən/
rhymes with -eɪʃən
CMU ARPABET:D IH0 S EH2 L ER0 EY1 SH AH0 N
Digits mark lexical stress: 1 primary, 2 secondary, 0 unstressed.
1
noun
Meaning 1
The act or process of decelerating.
Definition source: English Wiktionary via Wiktextract
Usage: uncountable
Examples
The rocket is now in deceleration.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
2
noun
Meaning 2
The amount by which a speed or velocity decreases (and so a scalar quantity or a vector quantity), an acceleration having a negative numerical value.
Definition source: English Wiktionary via Wiktextract
Usage: countable
Examples
The brakes produce a deceleration of 10 metres per second.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
3
noun
Meaning 3
the act of decelerating; decreasing the speed
Definition source: Princeton WordNet 3.0
Examples
he initiated deceleration by braking
Meaning relationships
Synonyms: none provided
Antonyms: acceleration
Broader terms: speed, speeding, hurrying
4
noun
Meaning 4
a decrease in rate of change
Definition source: Princeton WordNet 3.0
Examples
the deceleration of the arms race
Meaning relationships
Synonyms: slowing, retardation
Antonyms: acceleration
Broader terms: change, alteration, modification
5
noun
Meaning 5
(physics) a rate of decrease in velocity
Definition source: Princeton WordNet 3.0
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: none provided
Antonyms: acceleration
Broader terms: rate
History
Etymology
From de- + (ac)celeration.
Across languages
Translations
38 source translations are retained for this English entry.
Arabic:
تَباطُؤ
(tabāṭuʔ)
— the act or process of decelerating
Catalan:
desacceleració
— the act or process of decelerating
Catalan:
desceleració
— the act or process of decelerating
Chinese Mandarin:
減速 /减速
(jiǎnsù)
— the act or process of decelerating
Czech:
zpomalení
— the act or process of decelerating
Dutch:
vertraging
— the act or process of decelerating
Finnish:
hidastaminen
— the act or process of decelerating
Finnish:
hidastus
— the act or process of decelerating
French:
décélération
— the act or process of decelerating
German:
Verlangsamung
— the act or process of decelerating
Greek:
επιβράδυνση
(epivrádynsi)
— the act or process of decelerating
Hungarian:
lassulás
— the act or process of decelerating
Indonesian:
perlambatan
— the act or process of decelerating
Italian:
decelerazione
— the act or process of decelerating
Japanese:
減速
(gensoku)
— the act or process of decelerating
Māori:
whakapōturitanga
— the act or process of decelerating
Persian:
واشتاب
(vâšetâb)
— the act or process of decelerating
Polish:
zwalnianie
— the act or process of decelerating
Portuguese:
desaceleração
— the act or process of decelerating
Russian:
торможе́ние
(tormožénije)
— the act or process of decelerating
Russian:
замедле́ние
(zamedlénije)
— the act or process of decelerating
Russian:
децелера́ция
(decelerácija)
— the act or process of decelerating
Serbo-Croatian:
децелера́ција
— the act or process of decelerating
Serbo-Croatian:
decelerácija
— the act or process of decelerating
Spanish:
desaceleración
— the act or process of decelerating
Tagalog:
hidarasig
— the act or process of decelerating
Ukrainian:
спові́льнення
(spovílʹnennja)
— the act or process of decelerating
Finnish:
hidastuvuus
— amount by which a speed or velocity decreases
Greek:
επιβράδυνση
(epivrádynsi)
— amount by which a speed or velocity decreases
Indonesian:
deselerasi
— amount by which a speed or velocity decreases
Indonesian:
perlambatan
— amount by which a speed or velocity decreases
Malay:
nyahpecutan
— amount by which a speed or velocity decreases
Māori:
whakapōturitanga
— amount by which a speed or velocity decreases
Portuguese:
desaceleração
— amount by which a speed or velocity decreases
Russian:
децелера́ция
(decelerácija)
— amount by which a speed or velocity decreases
Serbo-Croatian:
децелера́ција
— amount by which a speed or velocity decreases
Serbo-Croatian:
decelerácija
— amount by which a speed or velocity decreases
Tagalog:
hidarasig
— amount by which a speed or velocity decreases