资料来源 : Webster's Revised Unabridged Dictionary (1913)

Threader \Thread"er\, n.
   1. A device for assisting in threading a needle.

   2. A tool or machine for forming a thread on a screw or in a
      nut.

资料来源 : WordNet®

threader
     n : a blunt needle for threading ribbon through loops [syn: {bodkin}]