'co-worker' definitions:

Definition of 'co-worker'

(from WordNet)
noun
An associate that one works with [syn: colleague, co- worker, fellow worker, workfellow]

Definition of 'co-worker'

From: GCIDE
  • co-worker \co`-work"er\, coworker \co`work"er\(k?`w?rk"?r), n. One who works with another; a cooperator.
  • Syn: colleague, coworker, fellow worker, fellow-worker, workfellow. [1913 Webster + WordNet 1.5]