lengthened vs elongated

lengthened and elongated both are adjectives.

Word	Noun	Adjective	Verb	Adverb
lengthened	No	Yes	No	No
elongated	No	Yes	No	No

As adjectives, lengthened and elongated are synonyms defined as:

Other synonyms of lengthened include extended, prolonged.

lengthened (adjective)	elongated (adjective)
drawn out or made longer spatially	having notably more length than width; being long and slender
	drawn out or made longer spatially