sentience vs mental faculty

sentience and mental faculty both are nouns.

Word	Noun	Adjective	Verb	Adverb
sentience	Yes	No	No	No
mental faculty	Yes	No	No	No

As nouns, mental faculty is a hypernym of sentience; that is, mental faculty is a word with a broader meaning than sentience:

sentience: the faculty through which the external world is apprehended
mental faculty: one of the inherent cognitive or perceptual powers of the mind

Other hypernyms of sentience include faculty, module.

sentience (noun)	mental faculty (noun)
the readiness to perceive sensations; elementary or undifferentiated consciousness	one of the inherent cognitive or perceptual powers of the mind
the faculty through which the external world is apprehended
state of elementary or undifferentiated consciousness