ra

1 of 4

abbreviation (1)

range

Ra

2 of 4

noun

ˈrä

: the Egyptian sun god and chief deity

Ra

3 of 4

symbol

radium

RA

4 of 4

abbreviation (2)

1

regular army

2

research assistant

3

residence assistant; resident assistant

4

rheumatoid arthritis

5

right ascension

6

Royal Academician; Royal Academy

Word History

Etymology

Noun

Egyptian rʽ

First Known Use

Noun

1877, in the meaning defined above

Time Traveler

The first known use of ra was in 1877

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Browse Nearby Words

R

ra

Ra

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Cite this Entry

Style

“Ra.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ra. Accessed 30 Oct. 2025.

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Medical Definition

Ra

1 of 2 symbol

radium

RA

2 of 2 abbreviation

rheumatoid arthritis

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