Man·cu·ni·an (măn-kyū'nē-ən, -kyūn'yən)
adj.
Of or relating to Manchester, England.

n.
A native or inhabitant of Manchester, England.

[From Latin Mancunium, Manchester, of Celtic origin.]


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The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2000 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.
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I was interested in checking this to find another (comparatively rare) example of a Celtic word subsumed into Latin and thence into English, so thanks for getting me to look, Jackie!