🇺🇸
/ˈæksɪs/
🇺🇸
/ˈæksɪs/
🇬🇧
/ˈæksəs/
🇬🇧
/ˈæksəs/
Plural
axes
An axis is an imaginary straight line that serves as a central reference for rotation, symmetry, or measurement — like the spine of a graph or the pole around which a planet spins. In math, it's one of the numbered lines (like x or y) that form the grid; in anatomy, it's the second cervical vertebra enabling head-turning.
The Earth rotates on its axis once every 24 hours.
In the Cartesian coordinate system, the x-axis runs horizontally and the y-axis runs vertically.
The butterfly's wings are perfectly symmetrical along the vertical axis.
Doctors examined the 'axis' vertebra to assess neck mobility after the injury.
When plotting data, always label both axes clearly to avoid confusion.
ax-
Comes from the Ancient Greek noun 'axōn' (ἀξών), meaning 'axis', 'shaft', or 'pivot'. It denotes a central line about which something rotates or is symmetrically arranged. This root appears in scientific, mathematical, and anatomical terms such as axial, axon, coaxial, and biaxial.