met·ro¹ (mĕt'rō)
n., pl., met·ros.
A subway system.

[French métro, short for (chemin de fer) métropolitain, metropolitan (railway), from Late Latin mētropolītānus. See metropolitan.]

met·ro² (mĕt'rō) Informal.
adj.
Metropolitan: metro Los Angeles.

n., pl., met·ros.
A metropolitan area: "This metro ranks number one in unemployment" (American Demographics).

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The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.

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