axis

1 of 2

noun

ax·​is ˈak-səs How to pronounce axis (audio)
plural axes ˈak-ˌsēz How to pronounce axis (audio)
1
a
: 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
6
a
: 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

Axis

2 of 2

adjective

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

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
As well as Earth’s axis being side-on to the sun at the equinox — which occurred on Sunday — the magnetic fields of Earth and the solar wind are also briefly aligned, causing cracks through which charged particles can accelerate for more intense displays of aurora. Jamie Carter, Forbes, 24 Sep. 2024 The Case Against Israeli-Saudi Normalization A deal won’t forge a two-state solution or push China out of the Middle East. Israel and the Coming Long War To Defeat Iran’s resistance axis, the IDF needs a new strategy—and a unified country. Michael W. Manulak, Foreign Affairs, 24 Sep. 2024
Adjective
The agency, among its many worries, feared that the Axis powers were at work on biological weapons that would use rats as vectors. Elizabeth Kolbert, The New Yorker, 30 Sep. 2024 But the menu also includes Axis venison, brisket tacos, ceviche and Shiner Bock beer bread. Bud Kennedy, Fort Worth Star-Telegram, 23 July 2024 See all Example Sentences for axis 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'axis.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

Noun

Middle English, "imaginary line passing through the center of a body, celestial axis," borrowed from Latin, "axletree, axle, chariot, celestial axis," going back to Indo-European *h2eḱs- "axle," whence also, with varying thematic derivation, Germanic *ahsō (whence Old English eax "axle," Old Saxon & Old High German ahsa), Old Russian/Eastern Church Slavic osĭ "axle," Bosnian-Croatian-Serbian ôs, Lithuanian ašìs, Old Prussian assis, Greek axon-, áxōn, Sanskrit ákṣaḥ, Avestan aša- "armpit"

Note: The Indo-European base *h2eḱs- also has derivatives with a suffixal l, for which see ala, axletree; compare also Welsh echel "axle, pivot," Breton ahel, which may go back to *akselā. The various thematic forms and extensions of h2eḱs- may reflect a root noun rather than an i-stem as in Latin; see E. Hamp, "Refining Indo-European Lexical Entries," Zeitschrift für vergleichende Sprachforschung, 95. Band, 1. Heft (1981), pp. 81-83. The original meaning of the noun may have been "shoulder joint"—if so, Avestan would be the only language to preserve this sense. It has been suggested that *h2eḱs- was formed by a "root extension" -s- from the verbal base *h2eǵ- "drive (cattle, etc.), set in motion (see agent).

First Known Use

Noun

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

Adjective

1938, in the meaning defined above

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

Dictionary Entries Near axis

Cite this Entry

“Axis.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/axis. Accessed 15 Oct. 2024.

Kids Definition

axis

noun
ax·​is ˈak-səs How to pronounce axis (audio)
plural axes ˈak-ˌsēz How to pronounce axis (audio)
1
a
: 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

called also axis of symmetry

c
: one of the reference lines of a coordinate system
2
a
: a bodily structure around which parts are arranged in a symmetrical way
b
: the main stem of a plant from which leaves and branches arise

Medical Definition

axis

noun
ax·​is ˈak-səs How to pronounce axis (audio)
plural axes -ˌsēz How to pronounce axis (audio)
1
a
: 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
2
a
: 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

More from Merriam-Webster on axis

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