kooky (adj.)youdaoicibaDictYouDict[kooky 词源字典]
1959, American English, originally teenager or beatnik slang, possibly a shortening of cuckoo.
Using the newest show-business jargon, Tammy [Grimes] admits, "I look kooky," meaning cuckoo. ["Life" magazine, Jan. 5, 1959]
Related: Kookily; kookiness.[kooky etymology, kooky origin, 英语词源]