midriff vs tissue layer

midriff and tissue layer both are nouns.

Word	Noun	Adjective	Verb	Adverb
midriff	Yes	No	No	No
tissue layer	Yes	No	No	No

As nouns, tissue layer is a hypernym of midriff; that is, tissue layer is a word with a broader meaning than midriff:

midriff: (anatomy) a muscular partition separating the abdominal and thoracic cavities; functions in respiration
tissue layer: a pliable sheet of tissue that covers or lines or connects the organs or cells of animals or plants

Other hypernyms of midriff include membrane, muscle system, muscular structure, musculature.

midriff (noun)	tissue layer (noun)
(anatomy) a muscular partition separating the abdominal and thoracic cavities; functions in respiration	a pliable sheet of tissue that covers or lines or connects the organs or cells of animals or plants
the middle area of the human torso (usually in front)