Apocryphal, a.
1. Pertaining to the Apocrypha.
2. Not canonical. Hence: Of doubtful authority; equivocal; mythic; fictitious; spurious; false. The passages . . . are, however, in part from apocryphal or fictitious works. Sir G. C. Lewis.
Shades of meaning
Fernald lists apocryphal only as an antonym, under authentic.
He lists it without comment; the entries above explain its neighbors.
Synonyms
none given