preoccupancy vs engrossment

preoccupancy and engrossment both are nouns.

Word	Noun	Adjective	Verb	Adverb
preoccupancy	Yes	No	No	No
engrossment	Yes	No	No	No

As nouns, preoccupancy and engrossment are synonyms defined as:

preoccupancy and engrossment: the mental state of being preoccupied by something

Other synonyms of preoccupancy include absorption, preoccupation.

preoccupancy (noun)	engrossment (noun)
the act of taking occupancy before someone else does	the quality of being intent and concentrated
the mental state of being preoccupied by something	the mental state of being preoccupied by something
	complete attention; intense mental effort