sense impression vs sense datum

sense impression and sense datum both are nouns.

Word	Noun	Adjective	Verb	Adverb
sense impression	Yes	No	No	No
sense datum	Yes	No	No	No

As nouns, sense impression and sense datum are synonyms defined as:

sense impression and sense datum: an unelaborated elementary awareness of stimulation

Other synonyms of sense impression include aesthesis, esthesis, sensation, sense experience.

sense impression (noun)	sense datum (noun)
an unelaborated elementary awareness of stimulation	an unelaborated elementary awareness of stimulation