expression, i-adjective
one could say; it wouldn't be wrong to say; it could be said that
A double-negative expression meaning 'it is not impossible to say,' used to cautiously assert something, often as 〜と言えなくもない.
彼の言い分も、わかると言えなくもない。
I could say I understand his point of view.
この映画は傑作と言えなくもない。
It wouldn't be wrong to call this movie a masterpiece.