humdrum vs sameness

humdrum and sameness both are nouns.

Word	Noun	Adjective	Verb	Adverb
humdrum	Yes	Yes	No	No
sameness	Yes	No	No	No

As nouns, humdrum and sameness are synonyms defined as:

humdrum and sameness: the quality of wearisome constancy, routine, and lack of variety

Other synonyms of humdrum include monotony.

humdrum (noun)	sameness (noun)
the quality of wearisome constancy, routine, and lack of variety	the quality of being alike
	the quality of wearisome constancy, routine, and lack of variety

humdrum (adjective)	sameness (adjective)
tediously repetitious or lacking in variety
not challenging; dull and lacking excitement