one sandwich short of a picnic

one sandwich short of a picnic

A pejorative phrase meaning not very intelligent or of questionable mental capacity. It can appear in many different forms and variations (for example: one card short of a full deck, one brick shy of a full load, etc.). He says he's going to start a business selling bees as pets—I think he may be one sandwich short of a picnic. The new manager is nice enough, but he's one sandwich short of a picnic, if you ask me.
See also: of, one, picnic, sandwich, short
Farlex Dictionary of Idioms.

one sandwich short of a picnic

Inf. not very smart; lacking intelligence. (Jocular.) Poor Bob just isn't too bright. He's one sandwich short of a picnic. She's not stupid. Just one sandwich short of a picnic.
See also: of, one, picnic, sandwich, short
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.

one sandwich short of a picnic

INFORMAL
If you say someone is one sandwich short of a picnic, you mean they are stupid or crazy. His daughter confirmed that her father was definitely one sandwich short of a picnic. Note: This expression is very variable. People often replace sandwich and picnic with other nouns, and one with a few. The guy was obviously several cards short of a full deck. Miss Martin is clearly one tent peg short of a full set. Note: These expressions are used humorously.
See also: of, one, picnic, sandwich, short
Collins COBUILD Idioms Dictionary, 3rd ed.

a sandwich (or two sandwiches) short of a picnic

(of a person) stupid or crazy. informal
See also: of, picnic, sandwich, short
Farlex Partner Idioms Dictionary
See also:
  • a few bricks short of a (full) load
  • a few sandwiches short of a picnic
  • a few, two, etc. bricks short of a load
  • a sandwich short of a picnic
  • bricks shy of a load
  • few bricks short of a load
  • one brick shy of a (full) load
  • one brick shy of a load
  • picnic
  • sandwich
References in periodicals archive
It's a serious subject, so why are there so many comical, food-related terms for it, like crackers, fruitcake and being one sandwich short of a picnic?
TV IRELAND: Mad about the words - PICK OF THE DAY BALDERDASH & PIFFLE BBC2, 10pm
Is he a potential murderer, the victim of a bad upbringing, one sandwich short of a picnic or just a no-good scally?
Good bar the script
Ordering psychiatric reports, he said: ``This poor defendant is more than one sandwich short of a picnic.''
`Picnic' jibe lands judge in hot water