THINK YOU’VE GOT A HANDLE ON THIS US STATE NICKNAME QUIZ?
Origin of stackup
Words nearby stackup
Idioms and Phrases with stackup
Measure up, equal, as in Their gift doesn't stack up against mine. This usage alludes to piling up one's chips at poker, and comparing them to those of the other players. [Early 1900s]
Make sense, seem plausible, as in Her explanation just doesn't stack up. Also see add up, def. 2.