1462, "box, case," from O.Fr. tronc "alms box in a church" (12c.), also "trunk of a tree, trunk of the human body," from L. truncus, originally "mutilated, cut off." The meaning "box, case" is likely to be from the notion of the body as the "case" of the organs. Eng. acquired the other two senses of the O.Fr. word later; sense of "main stem of a tree" dates from 1490; that of "torso of a human body" from 1494. The sense of "luggage compartment of a motor vehicle" is from 1930. The use in reference to an elephant's snout is from 1565, probably from confusion with trump (short for trumpet). Railroad trunk line is attested from 1843; telephone version is from 1889.