masking vs sense datum

masking and sense datum both are nouns.

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

As nouns, sense datum is a hypernym of masking; that is, sense datum is a word with a broader meaning than masking:

masking: the blocking of one sensation resulting from the presence of another sensation
sense datum: an unelaborated elementary awareness of stimulation

Other hypernyms of masking include aesthesis, esthesis, sensation, sense experience, sense impression.

masking (noun)	sense datum (noun)
the act of concealing the existence of something by obstructing the view of it	an unelaborated elementary awareness of stimulation
scenery used to block the audience's view of parts of the stage that should not be seen
the blocking of one sensation resulting from the presence of another sensation