The Collaborative International Dictionary of English v.0.48:

Raiser \Rais"er\ (r[=a]z"[~e]r), n.
   One who, or that which, raises (in various senses of the
   verb).
   [1913 Webster]

WordNet (r) 3.0 (2006):

raiser
    n 1: a bridge partner who increases the partner's bid
    2: someone concerned with the science or art or business of
       cultivating the soil [syn: agriculturist,
       agriculturalist, cultivator, grower, raiser]

Moby Thesaurus II by Grady Ward, 1.0:

93 Moby Thesaurus words for "raiser":
   Bauer, agriculturalist, agriculturist, agrologist, agronomist,
   ancestors, apprentice, architect, artificer, artist, author,
   begetter, beginner, builder, coffee-planter,
   collective farm worker, conceiver, constructor, craftsman, creator,
   crofter, cropper, cultivator, designer, deviser, dirt farmer,
   discoverer, dry farmer, effector, engenderer, engineer, executor,
   executrix, farm laborer, farmer, farmhand, father, founder,
   generator, gentleman farmer, granger, grower, harvester,
   harvestman, haymaker, husbandman, inaugurator, industrialist,
   initiator, instigator, institutor, introducer, inventor,
   journeyman, kibbutznik, kolkhoznik, kulak, maker, manufacturer,
   master, master craftsman, mother, muzhik, organizer, originator,
   past master, peasant, peasant holder, picker, planner, planter,
   plowboy, plowman, precursor, prime mover, producer, rancher,
   ranchman, realizer, reaper, rustic, shaper, sharecropper, sire,
   smith, sower, tea-planter, tenant farmer, tiller, tree farmer,
   truck farmer, wright, yeoman