longitudinal

lon·gi·tu·di·nal

adj
\ˌlän-jə-ˈtüd-nəl, -ˈtyüd-, -ˈt(y)ü-d^ən-əl, British also ˌläŋ-gə-\

Definition of LONGITUDINAL

1

: placed or running lengthwise

2

: of or relating to length or the lengthwise dimension

3

: involving the repeated observation or examination of a set of subjects over time with respect to one or more study variables

— lon·gi·tu·di·nal·ly adverb

Examples of LONGITUDINAL

1. The insect's body is black with yellow longitudinal stripes.
2. calculating the longitudinal position of a ship
3. a longitudinal study of career aspirations among girls from 5 to 17

First Known Use of LONGITUDINAL

15th century