I. |länjə|tüd ə nəl, -ə.tyü- adjective
Etymology: French, from Middle French, from Latin longitudin-, longitudo longitude + Middle French -al
1. : of or relating to the lengthwise dimension : axial
the longitudinal extent of the building
longitudinal stability
the longitudinal strength of a beam
2.
a. : extending in length : placed or running lengthwise — opposed to transverse
contour plowing has largely replaced longitudinal plowing on sloping land
b. : extending along or relating to the anteroposterior axis of a body or part
a fish with yellow longitudinal stripes
c. : ectomorphic
3. : extending over a period of time ; specifically : dealing with the growth and change of an individual or group over a period of years
a longitudinal study of juvenile delinquents over a five-year period
• lon·gi·tu·di·nal·ly - ə nəlē, -li adverb
II. noun
( -s )
1. : a longitudinally located body part (as a sinus or nerve)
2. : longeron
3. : one of the fore-and-aft continuous or intercostal girders used in large merchant ships and in nearly all warships to give the required strength and stiffness