late 15c., "slave," from M.Fr. serf, from L. servum (nom. servus) "slave" (see serve). Fallen from use in original sense by 18c. Meaning "lowest class of cultivators of the soil in continental European countries" is from 1610s. Use by modern writers with reference to medieval
Europeans first recorded 1761 (contemporary Anglo-L. records used nativus, villanus or servus). Serfdom first attested 1850.