The Collaborative International Dictionary of English v.0.48:
Visualizer \Vis"u*al*iz`er\, n. One who visualizes or is proficient in visualization; esp. (Physiol.), one whose mental imagery is prevailingly visualization. [Webster 1913 Suppl.]WordNet (r) 3.0 (2006):
visualizer n 1: one whose prevailing mental imagery is visual [syn: visualizer, visualiser]