Dictionary
1r
noun, often capitalized often attributive \ˈär\
: the 18th letter of the English alphabet
plural r's or rs \ˈärz\
Full Definition of R
1
a : the 18th letter of the English alphabet b : a graphic representation of this letter c : a speech counterpart of orthographic r
2
: a graphic device for reproducing the letter r
3
: one designated r especially as the 18th in order or class
4
: something shaped like the letter R
See r defined for English-language learners
See r defined for kids
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First Known Use of R
before 12th century
2r
abbreviation
Definition of R
1
radius
2
rain
3
range
4
rare
5
real
6
recto
7
red
8
repeat
9
rerun
10
resistance
11
right
12
roentgen
13
rook
14
rough
15
run
See r defined for English-language learners
1R
abbreviation
Definition of R
1
rabbi
2
radial
3
radical —used especially of a monovalent hydrocarbon radical
4
Rankine
5
Reaumur
6
recipe
7
registered trademark —often enclosed in a circle
8
regular
9
Republican
10
river
11
R-value
See R defined for English-language learners
2R
certification mark
Definition of R
R Defined for Kids
r
noun , often cap \ˈär\
plural r's or rs \ˈärz\
Definition of R for Kids
: the 18th letter of the English alphabet
R
abbreviation
Definition of R for Kids
regular
Medical Dictionary
r
abbreviation
Medical Definition of R
roentgen
Learn More About R
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Seen & Heard
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