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]