bi·month·ly (bī-mŭnth'lē)
adj.

1. Happening every two months.
2. Happening twice a month; semimonthly.

adv.

1. Once every two months.
2. Twice a month; semimonthly.

n., pl., -lies.
A bimonthly publication. See Usage Note at bi-¹.

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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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