Strong's G418 — ἀνένδεκτος (adjective)
anendektos (an-en'-dek-tos) adj.
1. unadmitted
2. (by implication) not supposable
[from G1 (as a negative particle) and a derivative of the same as G1735]
KJV: impossible 
Root(s): G1, G1735 
Hebrew root: ἐνδέχεται
Occurrences: 1