(also less frequent un·mis·take·able ) / ˌʌnmɪˈsteɪkəbl; NAmE / adjective
that cannot be mistaken for sb/sth else :
Her accent was unmistakable.
the unmistakable sound of gunfire
► un·mis·tak·ably (also less frequent un·mis·take·ably ) / -əbli; NAmE / adverb :
His accent was unmistakably British.