a few bricks shy/short of a load

a few bricks shy/short of a load

A pejorative phrase meaning not very intelligent or of questionable mental capacity. It can appear in many different forms and variations (for example: a few sandwiches short of a picnic, a few cards shy of a full deck, etc.). He says he's going to start a business selling bees as pets—I think he may be a few bricks shy of a load.
See also: brick, few, load, of, short, shy
Farlex Dictionary of Idioms.

bricks shy of a load

Mentally impaired, either unintelligent or merely eccentric. For example, He may be handsome but he's not too bright-a few bricks shy of a load. This term, transferring a light load to lightweight mental capacity, is usually preceded by either a few or a specific number such as two . [Slang; 1960s]
See also: brick, load, of, shy
The American Heritage® Dictionary of Idioms by Christine Ammer.

a few, two, etc. ˌbricks short of a ˈload

(also a few, two, etc. ˌsandwiches short of a ˈpicnic) (informal) (of a person) not very intelligent; slightly crazy: If you ask me, I think he must be one or two sandwiches short of a picnic! OPPOSITE: all there
The structure a few, two, etc....short of a(n)... is often used to make new idioms, for example a few cards short of a deck, a few letters short of an alphabet.
See also: brick, load, of, 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
  • few bricks short of a load
  • one brick shy of a (full) load
  • one brick shy of a load
  • one sandwich short of a picnic
  • picnic
  • sandwich