Quiz: Remember the definition of mal de mer?
early 14c., "to sin against (someone)," from Old French ofendre "transgress, antagonize," and directly from Latin offendere "to hit, strike against," figuratively "to stumble, commit a fault, displease, trespass against, provoke," from ob "against" (see ob-) + -fendere "to strike" (found only in compounds; see defend).
Meaning "to violate (a law), to make a moral false step, to commit a crime" is from late 14c. Meaning "to wound the feelings" is from late 14c. The literal sense of "to attack, assail" is attested from late 14c.; this has been lost in Modern English, but is preserved in offense and offensive. Related: Offended; offending.