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1. Latin oculus sinister (left eye)
2. old series
3. or o/s out of stock

old style

1. Printing A style of type originating in the 1700s and characterized by slight contrast between light and heavy strokes and slanting serifs.
2. Old Style Abbr. OS or O/S The method of reckoning dates according to the Julian calendar.

os 1

n. pl. o·ra (ôr′ə)
A mouth or an opening.

[Latin ōs, mouth; see ōs- in Indo-European roots.]

os 2

n. pl. os·sa (ŏs′ə)
A bone.

[Latin, bone; see ost- in Indo-European roots.]

os 3

n. pl. os·ar (ō′sär′)
See esker.

[Swedish ås, ridge, from Old Norse āss.]


The symbol for osmium.


1. or O/S Old Style
2. operating system
3. ordinary seaman
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.


ABBR (Comm) =outsizede tamaño extraordinario
Collins Spanish Dictionary - Complete and Unabridged 8th Edition 2005 © William Collins Sons & Co. Ltd. 1971, 1988 © HarperCollins Publishers 1992, 1993, 1996, 1997, 2000, 2003, 2005