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Synonyms for Round The Bend (same or very similar meaning)

WordNet sense 1 (informal or slang terms for mentally irregular):
balmy, batty, bonkers, buggy, cracked, crackers, daft, dotty, fruity, haywire, kooky, loco, loony, loopy, nuts, nutty, wacky, barmy, kookie, whacky, around the bend, bats

WordNet sense 2 (afflicted with or characteristic of mental derangement):

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