mid-15c., enfrangen, "to violate," from Latin infringere "to damage, break off, break, bruise," from in- "in" (see in- (2)) + frangere "to break" (see fraction). Meaning of "encroach" first recorded c. 1760. Related: Infringed; infringing.[infringe etymology, infringe origin, 英语词源]