WordNet (r) 3.0 (2006):

farmhand
    n 1: a hired hand on a farm [syn: farmhand, fieldhand,
         field hand, farm worker]

Moby Thesaurus II by Grady Ward, 1.0:

44 Moby Thesaurus words for "farmhand":
   Bauer, agriculturalist, agriculturist, agrologist, agronomist,
   coffee-planter, collective farm worker, crofter, cropper,
   cultivator, dirt farmer, dry farmer, farm laborer, farmer,
   gentleman farmer, granger, grower, harvester, harvestman, haymaker,
   husbandman, kibbutznik, kolkhoznik, kulak, muzhik, peasant,
   peasant holder, picker, planter, plowboy, plowman, raiser, rancher,
   ranchman, reaper, rustic, sharecropper, sower, tea-planter,
   tenant farmer, tiller, tree farmer, truck farmer, yeoman