locator (n.) Look up locator at Dictionary.com
c. 1600, "one who lets (something) for hire," a legal term, from Latin locator "one who lets," agent noun from locare "to put, place, set," from locus "a place" (see locus). As "one who settles upon land by legal right of possession," 1803, American English. Of things which locate, from 1902.