\ ˈäs \
plural ossa\ ˈä-​sə \

Definition of os

 (Entry 1 of 4)

: bone
\ ˈōs \
plural ora\ ˈȯr-​ə \

Definition of os (Entry 2 of 4)

Os

symbol

Definition of Os (Entry 3 of 4)

osmium

Definition of OS (Entry 4 of 4)

1 [ Latin oculus sinister ] left eye
2 Old Style
3 operating system
4 out of stock

First Known Use of os

Noun (1)

15th century, in the meaning defined above

Noun (2)

1737, in the meaning defined above

History and Etymology for os

Noun (1)

Latin oss-, os — more at osseous

Noun (2)

Latin or-, os — more at oral

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Dictionary Entries near os

Oryzopsis

Oryzorictes

orzo

os

OS

Os

Osage

Statistics for os

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Time Traveler for os

The first known use of os was in the 15th century

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More Definitions for os

os

noun
\ ˈäs \
plural ossa\ ˈäs-​ə \

Medical Definition of os

 (Entry 1 of 4)

: bone — see os calcis, os coxae

os

noun
\ ˈōs \
plural ora\ ˈōr-​ə, ˈȯr-​ə \

Medical Definition of os (Entry 2 of 4)

Os

symbol

Medical Definition of Os (Entry 3 of 4)

osmium

Medical Definition of OS (Entry 4 of 4)

left eye used in writing prescriptions

History and Etymology for os

Abbreviation

Latin oculus sinister

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More from Merriam-Webster on os

Rhyming Dictionary: Words that rhyme with os

Spanish Central: Translation of os

Nglish: Translation of os for Spanish Speakers

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