"inhabitant of Babylonia; a Chaldean," 1560s; see Babylon + -ian. From 1630s as an adjective. Earlier in the adjectival sense was Babylonical (1530s).
Entries linking to babylonian
Babylon
mid-14c., Babilon, representing the Greek rendition of Akkadian Bab-ilani "the gate of the gods," from bab "gate" + ilani, plural of ilu "god" (compare Babel). The Old Persian form, Babiru-, shows characteristic transformation of -l- to -r- in words assimilated from Semitic.
The English word also was formerly applied by Protestants to the Church in Rome, in reference to the woman "arrayed in purple and scarlet" in Revelation xvii.5 ("And upon her forehead was a name written, Mystery, Babylon the Great, the mother of harlots and abominations of the earth").
-ian
variant of suffix -an (q.v.), with connective -i-. From Latin -ianus, in which the -i- originally was from the stem of the word being attached but later came to be felt as connective. In Middle English frequently it was -ien, via French.