The Collaborative International Dictionary of English v.0.48:

Inventor \In*vent"or\, n. [L.: cf. F. inventeur.]
   One who invents or finds out something new; a contriver;
   especially, one who invents mechanical devices, new drugs,
   new processes, or other useful objects or procedures.
   [1913 Webster +PJC]

WordNet (r) 3.0 (2006):

inventor
    n 1: someone who is the first to think of or make something
         [syn: inventor, discoverer, artificer]

Moby Thesaurus II by Grady Ward, 1.0:

62 Moby Thesaurus words for "inventor":
   ancestors, apprentice, architect, artificer, artist, author,
   begetter, beginner, builder, conceiver, constructor, craftsman,
   creative artist, creator, designer, deviser, discoverer, effector,
   engenderer, engineer, executor, executrix, fancier, fantasist,
   fantast, father, founder, generator, grower, imaginer, inaugurator,
   industrialist, initiator, instigator, institutor, introducer,
   journeyman, maker, manufacturer, master, master craftsman, mother,
   mythicizer, mythifier, mythmaker, mythopoet, organizer, original,
   originator, past master, patriarch, planner, poet, precursor,
   prime mover, producer, raiser, realizer, shaper, sire, smith,
   wright



The Devil's Dictionary (1881-1906):

INVENTOR, n.  A person who makes an ingenious arrangement of wheels,
levers and springs, and believes it civilization.