mack vs oilskin

mack and oilskin both are nouns.

Word	Noun	Adjective	Verb	Adverb
mack	Yes	No	No	No
oilskin	Yes	No	No	No

As nouns, oilskin is a hyponym of mack; that is, oilskin is a word with a more specific, narrower meaning than mack:

mack: a waterproof raincoat made of rubberized fabric
oilskin: a macintosh made from cotton fabric treated with oil and pigment to make it waterproof

Other hyponyms of mack include slicker.

mack (noun)	oilskin (noun)
a waterproof raincoat made of rubberized fabric	a macintosh made from cotton fabric treated with oil and pigment to make it waterproof