ないでもないKind of, Might, Slightly, It’s not (impossible) that, Somewhat, In some respects

ないでもない, and なくもない are structures that have the literal meaning of 'to not not be (A)', and are used to express that something is 'a little (A)', or 'kinda (A)'. These structures are used primarily when the speaker can neither confirm or deny (A), but may also be used simply when not wanting to directly disagree with something that another person has said.

Both ないでもない and なくもない may be used after either the negated form of verbs, or nouns followed by the case marking particle が.

ないでもない and なくもない are completely interchangeable, with the primary difference simply being that なくもない is less frequently used. Additionally, ないものでもない may also be seen, but just like なくもない, it is far less common.