longitudinal
Running across a set direction of an object.
Example
“The motion about the longitudinal axis of an airplane is called roll.”
Other meanings
Running in the direction of the long axis of a body.
Relating to the geographical longitude.
Word history
From Latin "longitūdō".
Where this comes from
This definition is adapted from “longitudinal” on Wiktionary, by its contributors, published under CC BY-SA 4.0. This page is published under the same licence.