Old English swin "pig, hog, wild boar," from Proto-Germanic *swinan (cognates: Old Saxon, Old Frisian Middle Low German, Old High German swin, Middle Dutch swijn, Dutch zwijn, German Schwein, Old Norse, Swedish, Danish svin), neuter adjective (with suffix *-ino-) from PIE *su- "pig" (see sow, n.). The native word, largely ousted by pig. Applied to persons from late 14c. Phrase pearls before swine (mid-14c.) is from Matt. vii:6; an early English formation of it was:The Latin word in the Gospel verse was confused in French with marguerite "daisy" (the "pearl" of the field), and in Dutch the expression became "roses before swine." Swine-flu attested from 1921.