Dictionary
1x
noun, often capitalized often attributive \ˈeks\
: the 24th letter of the English alphabet
: the Roman numeral that means 10
mathematics —used to represent an unknown quantity
plural x's or xs \ˈek-səz\
Full Definition of X
1
a : the 24th letter of the English alphabet b : a graphic representation of this letter c : a speech counterpart of orthographic x
2
: ten — see number table
3
: a graphic device for reproducing the letter x
4
: one designated x especially as the 24th in order or class, or the first in an order or class that includes x, y, and sometimes z
5
: an unknown quantity
6
: something shaped like or marked with the letter X
See x defined for English-language learners
See x defined for kids
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First Known Use of X
before 12th century
2x
verb
x–ed also x'd or xed \ˈekst\ x–ing or x'ing \ˈek-siŋ\
Definition of X
transitive verb
1
: to mark with an x
2
: to cancel or obliterate with a series of x's —usually used with out <x-ed out the mistake>
See x defined for English-language learners
First Known Use of X
circa 1849
3x
abbreviation
Definition of X
1
cross
2
ex
3
experimental
4
extra
Other Physics Terms
X
adjective \ˈeks\
Definition of X
of a motion picture : of such a nature that admission is denied to persons under a specified age (as 17) —used before the adoption of NC-17
See X defined for kids First Known Use of X
1970
X'ING Defined for Kids
x
noun , often cap \ˈeks\
plural x's or xs \ˈek-səz\
Definition of X for Kids
1
: the 24th letter of the English alphabet
2
: ten in Roman numerals
3
: an unknown quantity <What is the value of x in the equation x + 2 = 6?>
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Seen & Heard
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