Meaning
from a negative, and dunatos, "able, strong," is used (a) of persons, Act 14:8, "impotent;" figuratively, Rom 15:1, "weak;" (b) of things, "impossible," Mat 19:26, Mar 10:27, Luk 18:27, Heb 6:4, Heb 6:18, Heb 10:4, Heb 11:6; in Rom 8:3, "for what the Law could not do," is, more lit., "the inability of the law;" the meaning may be either "the weakness of the Law," or "that which was impossible for the Law;" the latter is perhaps preferable; literalism is ruled out here, but the sense is that the Law could neither justify nor impart life.
signifies "inadmissible" (a, negative, n, euphonic, and endechomai, "to admit, allow"), Luk 17:1, of occasions of stumbling, where the meaning is "it cannot be but that they will come."
signifies "to be impossible" (corresponding to A, No. 1), "unable;" in the NT it is used only of things, Mat 17:20, "(nothing) shall be impossible (unto you);" Luk 1:37. AV "(with God nothing) shall be impossible;" RV, "(no word from God, a different construction in the best mss.) shall be void of power;" rhema may mean either "word" or "thing" (i.e., fact). In the Sept. the verb is always used of things and signifies either to be "impossible" or to be impotent, e.g., Gen 18:14, Lev 25:35, "he fail;" Deu 17:8, Job 4:4, "feeble;" Job 42:2, Dan 4:6, Zec 8:6.