longitudinally vs longways

longitudinally is not a noun while longways is a noun.

Word	Noun	Adjective	Verb	Adverb
longitudinally	No	No	No	Yes
longways	Yes	No	No	Yes

As adverbs, longitudinally and longways are synonyms defined as:

Other synonyms of longitudinally include lengthways, lengthwise, longwise.

longitudinally (noun)	longways (noun)
	country dancing performed with couples in two long lines facing each other

longitudinally (adverb)	longways (adverb)
with respect to longitude	in the direction of the length
in the direction of the length
across time