IPA: /ˈlɔːŋˌwaɪz/
KK: /lɔŋˌwaɪz/
In a direction that is long or along the length of something.
The fabric was cut longwise to create a longer piece for the dress.
Longwise → It is formed from "long" (from Old English "lang", meaning having a great distance from one end to the other) and "-wise" (meaning in the manner of or direction). The word "longwise" means in the direction or manner of length.
Think of something that is oriented 'in the direction of length' — 'long' refers to distance, and '-wise' indicates manner or direction.