colleague - Things Learned while reading "The Hound of the Baskervilles" - Sherlock Holmes

"It was all very confused. Sir Charles had evidently stood there for five or ten minutes."

"How do you know that?"

"Because the ash had twice dropped from his cigar."

"Excellent! This is a colleague, Watson, after our own heart.

colleague - Google Search

col·league/ˈkälēg/

Noun: A person with whom one works, esp. in a profession or business.