longitudinal

adj. of or pertaining to longitude or length; running lengthwise

The term, longitudinal means "along the major (or long) axis" as opposed to latitudinal which means "along the width", transverse, or across. In automotive engineering, a longitudinal engine is an engine in which the crankshaft is oriented along the long axis of the vehicle, front to back.Longitudinal waveLongitudinal studySee also: longitude
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Adjective
1. of or relating to lines of longitude; "longitudinal reckoning by the navigator"
(pertainym) meridian, longitude, line of longitude
2. running lengthwise; "a thin longitudinal strip"; "longitudinal measurements of the hull"
(similar) lengthwise, lengthways
3. over an extended time; "a longitudinal study of twins"
(similar) long

adj. lengthwise, longitudinal

adj. lengthwise, along the length; longitudinal, of or pertaining to longitude or length; running lengthwise