axis

noun

1.
a straight line through a body or figure that satisfies certain conditions
Derived from:
axial
2.
the main stem or central part about which plant organs or plant parts such as branches are arranged
3.
a group of countries in special alliance
bloc
4.
the 2nd cervical vertebra; serves as a pivot for turning the head
axis vertebra
5.
the center around which something rotates
axis of rotation
Derived from:
axial