The Collaborative International Dictionary of English v.0.48:
Threader \Thread"er\, n. 1. A device for assisting in threading a needle. [1913 Webster] 2. A tool or machine for forming a thread on a screw or in a nut. [1913 Webster]WordNet (r) 3.0 (2006):
threader n 1: a blunt needle for threading ribbon through loops [syn: bodkin, threader]