loony

From Wiktionary

Pronunciation[change]

Adjective[change]

Positive
loony

Comparative
loonier

Superlative
looniest

  1. (informal) If someone is loony, he or she is an insane person.

Noun[change]

Singular
loony

Plural
loonies

  1. (informal) A loony is an insane or foolish person.

Synonyms[change]