From The Collaborative International Dictionary of English v.0.48:
Copier \Cop"i*er\, n. [From. Copy.]
1. One who copies; one who writes or transcribes from an
original; a transcriber.
[1913 Webster]
2. An imitator; one who imitates an example; hence, a
plagiarist.
[1913 Webster]
3. a machine that makes copies of documents, especially by
xerography; a photocopier; as, to run twenty copies off on
the copier.
[PJC]