filmy (adj.)

Old English filmen "membrane, thin skin, foreskin," from West Germanic *filminjan (source also of Old Frisian filmene "skin," Old English fell "hide"), extended from Proto-Germanic *fello(m) "animal hide," from PIE root *pel- (3) "skin, hide."

Sense of "a thin coat of something" is 1570s, extended by 1845 to the coating of chemical gel on photographic plates. By 1895 this also meant the coating plus the paper or celluloid. Hence "a motion picture" (1905); sense of "film-making as a craft or art" is from 1920.

adjective suffix, "full of or characterized by," from Old English -ig, from Proto-Germanic *-iga- (source also of Dutch, Danish, German -ig, Gothic -egs), from PIE -(i)ko-, adjectival suffix, cognate with elements in Greek -ikos, Latin -icus (see -ic). Originally added to nouns in Old English; used from 13c. with verbs, and by 15c. even with other adjectives (for example crispy). Adjectives such as hugy, vasty are artificial words that exist for the sake of poetical metrics.