lunchy

[ luhn-chee ]
/ ˈlʌn tʃi /

adjective, lunch·i·er, lunch·i·est. Slang.

stupid; dull-witted.
carefree or irresponsible.

Origin of lunchy

1960–65; perhaps lunch (extracted from the idiom out to lunch dim-witted, irresponsible) + -y1
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019