ax·​is | \ ˈak-səs How to pronounce axis (audio) \
plural axes\ ˈak-​ˌsēz How to pronounce axes (audio) \

Definition of axis

 (Entry 1 of 2)

1a : a straight line about which a body or a geometric figure rotates or may be supposed to rotate the Earth's axis
b : a straight line with respect to which a body or figure is symmetrical the axis of a cone

called also axis of symmetry

c : a straight line that bisects at right angles a system of parallel chords of a curve and divides the curve into two symmetrical parts
d : one of the reference lines of a coordinate system (see coordinate entry 3 sense 1a)
2 anatomy
a : the second vertebra of the neck on which the head and first vertebra turn as on a pivot
b : any of various central, fundamental, or axial parts
3 botany : a plant stem
4 crystallography : one of several imaginary lines assumed in describing the positions of the planes by which a crystal is bounded and the positions of atoms in the structure of the crystal
5 : a main line of direction, motion, growth, or extension the axis of a city
6a : an implied line in painting or sculpture through a composition to which elements in the composition are referred fruit and flowers arranged about a diagonal axis
b : a line actually drawn and used as the basis of measurements in an architectural or other working drawing
7 aviation : any of three fixed lines of reference in an aircraft that run in the longitudinal, lateral, and vertical directions, are mutually perpendicular, and usually pass through the aircraft's center of gravity
8 : partnership, alliance an axis of countries
9 : a point or continuum on which something centers an axis of social power

Definition of Axis (Entry 2 of 2)

: of or relating to the three powers Germany, Italy, and Japan engaged against the Allied nations in World War II

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Examples of axis in a Sentence

Noun the Earth's axis of rotation the spin of the Earth on its axis
Recent Examples on the Web: Noun The Time axis extends from now all the way into the future. Time, "How the Bento Box Change Can Change How We See the World?," 5 Nov. 2019 Except, unlike a handspring, the touchdown raiz enables an athlete to gather rotational momentum about the axis that runs between their head and their feet. Wired, "How Ultra-Flexible Teens Turned ‘Tricking’ Into a Sport," 25 Oct. 2019 From this core, Killingsworth flexes his power as master of the axis point. R. Daniel Foster, Los Angeles Times, "Take a rare look inside architect Edward Killingsworth’s Long Beach home," 18 Oct. 2019 The horizontal axis measures the relative complexity of each country – the further to the right, the more complex. John Authers | Bloomberg, Washington Post, "Germany’s Inconvenient Truth? It’s Too Complicated," 14 Oct. 2019 On these days however the Earth’s axis is neither tilted away nor toward the sun, and both northern and southern hemispheres experience equal amounts of sunshine. Andrew Fazekas, National Geographic, "See Neptune at its best and more top stargazing in September," 1 Sep. 2019 After carrying out additional tests, the Soyuz slewed about its long axis before briefly lining up on the Poisk module docking port. William Harwood, CBS News, "Unpiloted Soyuz spacecraft aborts space station docking," 24 Aug. 2019 And over the long term that will likely underpin the Saudi-UAE axis as a counterweight to Iran. Tim Lister, CNN, "Cracks are appearing in the Mideast's most important alliance. That's bad news for Trump," 22 Aug. 2019 For instance, any change in the rate of Earth’s rotation around the Sun, or on its own axis, would be catastrophic, the Earth would become either too hot or too cold to support life. Steve Manning,, "Manning: God holds us together physically and spiritually, but also structurally," 9 Nov. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'axis.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of axis


14th century, in the meaning defined at sense 1a


1938, in the meaning defined above

History and Etymology for axis


Latin, axis, axle; akin to Old English eax axis, axle, Greek axōn, Lithuanian ašis, Sanskrit akṣaḥ

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Time Traveler for axis

Time Traveler

The first known use of axis was in the 14th century

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Statistics for axis

Last Updated

30 Nov 2019

Cite this Entry

“Axis.” The Dictionary, Merriam-Webster Inc., Accessed 11 December 2019.

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More Definitions for axis


How to pronounce Axis (audio)

English Language Learners Definition of axis

: the imaginary straight line that something (such as the Earth) turns around
: a straight line that divides a shape evenly into two parts


ax·​is | \ ˈak-səs How to pronounce axis (audio) \
plural axes\ ˈak-​ˌsēz \

Kids Definition of axis

1 : a straight line about which a body or a geometric figure rotates or may be thought of as rotating the earth's axis
2 : a line of reference used to assign numbers to locations in a geometric plane


ax·​is | \ ˈak-səs How to pronounce axis (audio) \
plural axes\ -​ˌsēz How to pronounce axes (audio) \

Medical Definition of axis

1a : a straight line about which a body or a geometric figure rotates or may be thought of as rotating
b : a straight line with respect to which a body, organ, or figure is symmetrical
2a : the second vertebra of the neck of the higher vertebrates that is prolonged anteriorly within the foramen of the first vertebra and united with the dens which serves as a pivot for the atlas and head to turn upon

called also epistropheus

b : any of various central, fundamental, or axial parts the cerebrospinal axis the skeletal axis
c : axilla

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More from Merriam-Webster on axis

Thesaurus: All synonyms and antonyms for axis

Rhyming Dictionary: Words that rhyme with axis

Spanish Central: Translation of axis

Nglish: Translation of axis for Spanish Speakers

Britannica English: Translation of axis for Arabic Speakers Encyclopedia article about axis

Comments on axis

What made you want to look up axis? Please tell us where you read or heard it (including the quote, if possible).


heavy with or as if with moisture

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