1557, in phrase jobbe of worke "piece of work" (contrasted with continuous labor), perhaps a variant of gobbe "mass, lump" (c.1400, see gob). Sense of "work done for pay" first recorded 1660. Slang meaning "specimen, thing, person" is from 1927. The verb is attested from 1670. On the job "hard at work" is from 1882. Jobber "one who does odd jobs" is from 1706. Job lot is from obsolete sense of "cartload, lump," which may also be ult. from gob.