LONGITU'DINAL, adjective 1. Pertaining to longitude or length; as longitudinal distance. 2. Extending in length; running lengthwise, as distinguished from transverse or across; as the longitudinal diameter of a body. The longitudinal suture of the head runs between the coronal and lamdoidal sutures.
Source: Webster's 1828 American Dictionary ↗ · public-domain · returned verbatim, no AI