The definition of crumby is having a lot of crumbs or is slang for miserable or cheap. An example of something crumby is a piece of cake with crumbs.

What does it mean to feel crumby?

: to feel sick or unhappy I felt crummy all day yesterday. I feel crummy about the way I treated her.

What does the term deficient mean?

(Entry 1 of 2) 1 : lacking in some necessary quality or element deficient in judgment bones deficient in calcium. 2 : not up to a normal standard or complement (see complement entry 1 sense 1b(1)) : defective deficient strength …