mortal sin vs laziness

mortal sin and laziness both are nouns.

Word	Noun	Adjective	Verb	Adverb
mortal sin	Yes	No	No	No
laziness	Yes	No	No	No

As nouns, laziness is a hyponym of mortal sin; that is, laziness is a word with a more specific, narrower meaning than mortal sin:

mortal sin: an unpardonable sin entailing a total loss of grace
laziness: apathy and inactivity in the practice of virtue (personified as one of the deadly sins)

mortal sin (noun)	laziness (noun)
an unpardonable sin entailing a total loss of grace	apathy and inactivity in the practice of virtue (personified as one of the deadly sins)
	relaxed and easy activity
	inactivity resulting from a dislike of work