adj
loony
LOO-nee
Loony (adj) means Crazy or mentally unstable. Example: “That's a completely loony idea.”
adj
1
Crazy or mentally unstable.
"That's a completely loony idea."
"He went a bit loony after weeks without sleep."
2
Extremely silly or ridiculous.
"The plot of the movie was loony but fun."
noun
1
An informal word for a foolish or unstable person.
"Only a loony would try to cross that river in a storm."
How to use loony
Learner’s notesIn plain EnglishCrazy, silly, or someone acting that way — used casually, often affectionately.
When to use it
Informal; can sound insensitive when applied to real mental illness, so it's mostly used for silly behaviour or ideas rather than clinical conditions.
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Word forms
- Plural
- loonies
- Comparative
- loonier
- Superlative
- looniest
Fill the gap
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That's a completely _____ idea.
Etymology
A shortened, informal version of "lunatic."
Synonyms
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Related words
Rhymes for loony
See all rhymes for loony →Frequently asked questions
What does “loony” mean?
The word “loony” means crazy or mentally unstable. In plain terms, crazy, silly, or someone acting that way — used casually, often affectionately.
How do you pronounce “loony”?
“Loony” is pronounced LOO-nee (/ˈluːni/ in IPA).
How do you use “loony” in a sentence?
Here is “loony” used in a sentence: “That's a completely loony idea.”
What part of speech is “loony”?
Depending on how it is used, “loony” can be an adjective and a noun.
How many meanings does “loony” have?
“Loony” has 3 distinct senses listed in this dictionary. The most common is: crazy or mentally unstable.
