Source : Webster's Revised Unabridged Dictionary (1913)

Raiser \Rais"er\, n.
   One who, or that which, raises (in various senses of the
   verb).

Source : WordNet®

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}, {cultivator},
        {grower}]