To be not very intelligent or of questionable mental capacity. This expression can appear in many different forms and variations (e.g., "a few sandwiches short of a picnic," "one brick short of a load.," etc.). He says he's going to start a business selling bees as pets—I think he may be several cards short of a deck. The new manager is nice enough, but he's several cards short of a full deck, if you ask me.

To be not very intelligent or of questionable mental capacity. This expression can appear in many different forms and variations (e.g., "a few sandwiches short of a picnic," "one brick short of a load.," etc.). He says he's going to start a business selling bees as pets—I think he may be several cards short of a full deck. The new manager is nice enough, but he's several cards short of a full deck, if you ask me.