WordNet (r) 3.0 (2006):

tenant farmer
    n 1: a farmer who works land owned by someone else

Moby Thesaurus II by Grady Ward, 1.0:

44 Moby Thesaurus words for "tenant farmer":
   Bauer, agriculturalist, agriculturist, agrologist, agronomist,
   coffee-planter, collective farm worker, crofter, cropper,
   cultivator, dirt farmer, dry farmer, farm laborer, farmer,
   farmhand, 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, tiller, tree farmer, truck farmer, yeoman