swine (n.) Look up swine at Dictionary.com
Old English swin "pig, hog, wild boar," from Proto-Germanic *swinan (source also of 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 Matthew vii.6; an early English formation of it was:
Ne ge ne wurpen eowre meregrotu toforan eowrum swynon. [c. 1000]
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.