Make Your Editor Cry: Axis (Awkward Plural)

Make Your Editor Cry:  Axis (Awkward Plural)

BLUF: (Bottom Line Up Front)
The plural of axis is axes.

axis: one of the reference lines of a coordinate system

The singular of axis is axis. The plural of axis is axes. Note the -e that replaces the -i.

The noun axis has a Greek root, which is the derivation of the plural axes. There is no alternative English plural form. Words like axises or making it a possessive axis’ or axis’s doesn’t work regardless of what style guide you may wish to consult. It’s axes.

Examples:

The point where the axes meet is called
the origin.
The axes of a two-dimensional Cartesian system
divide the plane into four infinite regions, called quadrants.

One final note. The plural of ax is also axes. No relation.