"grating, harsh, rough," 1670s, of plants; by 1821 of voices, from rasp + -y (2).
Entries linking to raspy
rasp v.
mid-13c., raspen, "to scrape, abrade by rubbing with a coarsely rough instrument or something like one," from Middle Dutch raspen and from Old French rasper (Modern French râper) "to grate, rasp," which is ultimately from a West Germanic source (compare Old English gehrespan, Old High German hrespan "to rake together") for which see raffle (n.). The vocalic sense is from 1843. Related: Rasped; rasping.
-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.