adj · 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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/ˈluːni/
Canada:Recorded audio is listed in the source snapshot.
rhymes with -uːni
homophone: loonie
homophone: looney
homophone: luny
CMU ARPABET:L UW1 N IY0
Digits mark lexical stress: 1 primary, 2 secondary, 0 unstressed.
1
adj
Meaning 1
Insane.
Definition source: English Wiktionary via Wiktextract
Usage: derogatory, informal, offensive
Examples
loony scheme
completely loony
They dismissed his loony ideas.
The movie is full of loony characters.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
2
adj
Meaning 2
Very silly, absurd.
Definition source: English Wiktionary via Wiktextract
Usage: derogatory, informal, offensive
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
3
noun
Meaning 3
An insane or very foolish person.
Definition source: English Wiktionary via Wiktextract
Usage: derogatory, informal, offensive
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
4
adjective satellite
Meaning 4
informal or slang terms for mentally irregular
Definition source: Princeton WordNet 3.0
Examples
it used to drive my husband balmy
Meaning relationships
Synonyms: balmy, barmy, bats, batty, bonkers, buggy, cracked, crackers, daft, dotty, fruity, haywire, kooky, kookie, loco, loopy, nuts, nutty, round the bend, around the bend, wacky, whacky
Antonyms: none provided
5
noun
Meaning 5
someone deranged and possibly dangerous
Definition source: Princeton WordNet 3.0
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: crazy, looney, nutcase, weirdo
Antonyms: none provided
Broader terms: lunatic, madman, maniac
History
Etymology
Shortened from lunatic, and likely also from loon ("rascal", and also the bird) + -y.
Across languages
Translations
34 source translations are retained for this English entry.
Bulgarian:
смахнат
(smahnat)
— insane
Bulgarian:
побъркан
(pobǎrkan)
— insane
Czech:
šílený
— insane
Czech:
bláznivý
— insane
Danish:
tosset
— insane
Danish:
gal
— insane
Danish:
vanvittig
— insane
Finnish:
hullu
— insane
Macedonian:
луд
(lud)
— insane
Russian:
сумасше́дший
(sumasšédšij)
— insane
Slovak:
šialený
— insane
Slovak:
bláznivý
— insane
Ottoman Turkish:
دلی
(deli)
— insane
Welsh:
lloerig
— insane
Bulgarian:
психар
(psihar)
— an insane or very foolish person
Bulgarian:
куку
(kuku)
— an insane or very foolish person
Czech:
blázen
— an insane or very foolish person
Danish:
tosse
— an insane or very foolish person
Danish:
galning
— an insane or very foolish person
Finnish:
hullu
— an insane or very foolish person
Finnish:
kahjo
— an insane or very foolish person
Finnish:
kaheli
— an insane or very foolish person
Irish:
gealt
— an insane or very foolish person
Macedonian:
лу́дак
(lúdak)
— an insane or very foolish person
Russian:
псих
(psix)
— an insane or very foolish person
Russian:
душевнобольной
(duševnobolʹnoj)
— an insane or very foolish person
Scottish Gaelic:
amadan
— an insane or very foolish person
Scottish Gaelic:
burraidh
— an insane or very foolish person
Slovak:
blázon
— an insane or very foolish person
Swedish:
galning
— an insane or very foolish person
Swedish:
knäppgök
— an insane or very foolish person
Swedish:
tokstolle
— an insane or very foolish person
Ottoman Turkish:
دلی
(deli)
— an insane or very foolish person
