apocryphalyoudaoicibaDictYouDict[apocryphal 词源字典]
apocryphal: [16] Apocryphal is a ‘secondgeneration’ adjective; the original adjective form in English was apocrypha (‘The writing is apocrypha when the author thereof is unknown’, John de Trevisa 1387). This came, via ecclesiastical Latin, from Greek apókruphos ‘hidden’, a derivative of the compound verb apokrúptein ‘hide away’, which was formed from the prefix apo- ‘away, off’ and the verb krúptein ‘hide’ (source of English crypt and cryptic).

It was applied as a noun to writings in general that were of unknown authorship, and in the 16th century came to be used specifically as the collective term for the uncanonical books of the Old Testament. It was perhaps confusion between the adjectival and nominal roles of apocrypha that led to the formation of the new adjective apocryphal towards the end of the 16th century.
=> crypt, cryptic[apocryphal etymology, apocryphal origin, 英语词源]
apocryphal (adj.)youdaoicibaDictYouDict
1580s, "of doubtful authenticity," from Apocrypha + -al (1). Middle English had apocrive (late 14c.) in same sense.