Meaning
"strong, mighty, powerful, able (to do)," in its neuter form signifies "possible," Mat 19:26, Mat 24:24, Mat 26:39, Mar 9:23, Mar 10:27, Mar 13:22, Mar 1:14-36, Luk 18:27, Act 2:24, Act 20:16 (Act 27:39, in some mss.; dunamai, "to be able," in the most authentic, RV, "they could"); Rom 12:18, Gal 4:15. See ABLE.
"to be," is used in the third person singular, impersonally, with the meaning "it is possible," negatively in 1Co 11:20, RV, (AV, "it is not"), and Heb 9:5, "we cannot," lit., "it is not possible."
Note: For Heb 10:4, AV, "it is not possible," see IMPOSSIBLE.