1872, of wood, from punk (n.1) + -y (2). Related: Punkiness.
Entries linking to punky
punk n.1
"Chinese incense," 1870, according to OED from punk (n.) "rotten wood used as tinder;" for which see punk (adj.).
-y 2
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.