lady's maid vs amah

lady's maid and amah both are nouns.

Word	Noun	Adjective	Verb	Adverb
lady's maid	Yes	No	No	No
amah	Yes	No	No	No

As nouns, amah is a hypernym of lady's maid; that is, amah is a word with a broader meaning than lady's maid:

Other hypernyms of lady's maid include housemaid, maid, maidservant.

lady's maid (noun)	amah (noun)
a maid who is a lady's personal attendant	a female domestic
	a woman hired to suckle a child of someone else