stretching vs enlargement

stretching and enlargement both are nouns.

Word	Noun	Adjective	Verb	Adverb
stretching	Yes	No	No	No
enlargement	Yes	No	No	No

As nouns, enlargement is a hypernym of stretching; that is, enlargement is a word with a broader meaning than stretching:

stretching: act of expanding by lengthening or widening
enlargement: the act of increasing (something) in size or volume or quantity or scope

Other hypernyms of stretching include expansion.

stretching (noun)	enlargement (noun)
exercise designed to extend the limbs and muscles to their full extent	the act of increasing (something) in size or volume or quantity or scope
act of expanding by lengthening or widening	a photographic print that has been enlarged
	a discussion that provides additional information
	the state of being enlarged