o.

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O.

abbr.
1. ocean
2. Ohio

o.

abbr.
1. Latin octarius (pint)
2. also O. octavo
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.