protuberance (n.)

1640s, "a swelling tumor on the body; anything swelled or pushed beyond the surrounding or adjacent surface," from Late Latin protuberantem (nominative protuberans), present participle of protuberare "to swell, bulge, grow forth," from Latin pro "forward" (see pro-) + tuber "lump, swelling" (from PIE root *teue- "to swell"). Meaning "fact or condition of swelling or pushing beyond the surrounding or adjacent surface" is by 1680s. Related: Protuberancy.