1.Lit. [of a container] not able to contain water without leaking. This old wading pool won't hold water any longer.
2.Fig. not able to be proved; not correct or true. Jack's story won't hold water. It sounds too unlikely.The police's theory will not hold water. The suspect has an ironclad alibi.
to not seem to be true or reasonable That argument isn't likely to hold water with my father!A lot of the stuff I believed in when I was 17 just doesn't hold water today.