Green’s Dictionary of Slang

stack up v.1

1. [late 19C] to challenge.

2. [late 19C–1900s] to meet.

3. [late 19C+] (also stack) to emerge, to develop, to maintain, to appear as it should; also in negative phr. that doesn’t/don’t stack up, that isn’t logical, that fails to reach a standard.

4. [20C+] to compare with; usu. as stack up to/against.

5. used of an indivual, to prove useful or dependable.