skycap vs porter

skycap and porter both are nouns.

Word	Noun	Adjective	Verb	Adverb
skycap	Yes	No	No	No
porter	Yes	No	Yes	No

As nouns, porter is a hypernym of skycap; that is, porter is a word with a broader meaning than skycap:

skycap (noun)	porter (noun)
a porter who helps passengers with their baggage at an airport	a very dark sweet ale brewed from roasted unmalted barley
	a person employed to carry luggage and supplies
	a railroad employee who assists passengers (especially on sleeping cars)
	someone who guards an entrance

skycap (verb)	porter (verb)
	carry luggage or supplies