loony
[adjective]
Synonyms: foolish, absurd, balmy, crazy, harebrained, insane, potty, preposterous, silly, wacky, batty, bananas, bonkers, crackbrained, daffy, fruity, lunatic, nutty
[noun]
Synonyms: lunatic, bedlamite, dement, loon, madling, madman, maniac, non compos, nut, Tom o' Bedlam

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English Thesaurus: crazy, mad, nuts, loony, insane, ...

[TahlilGaran] English Synonym Dictionary ▲

I. loon‧y¹ /ˈluːni/ noun (plural loonies) [countable]
[Date: 1800-1900; Origin: lunatic]
informal someone who is crazy or strange:
Her brother’s a complete loony.

[TahlilGaran] Dictionary of Contemporary English ▲

II. loony² adjective
informal silly, crazy, or strange:
a loony idea

[TahlilGaran] Dictionary of Contemporary English ▲

crazy very strange or not sensible – used about people, ideas, and behaviour:
People think I’m crazy when I start talking about ghosts.
It was a crazy thing to do.
mad British English crazy:
Are you mad?
Whose mad idea was that?
At first, everyone thought he was completely mad.
nuts informal (also bonkers British English) [not before noun] crazy:
The whole thing sounds completely nuts.
Have you gone bonkers?
loony informal crazy:
another loony suggestion
The man is totally loony.
insane completely crazy:
I know it sounds insane, but it’s true.

[TahlilGaran] English Thesaurus ▲