aid vs avail

aid and avail both are nouns.

Word	Noun	Adjective	Verb	Adverb
aid	Yes	No	Yes	No
avail	Yes	No	Yes	No

As verbs, avail is a hyponym of aid; that is, avail is a word with a more specific, narrower meaning than aid:

aid (noun)	avail (noun)
the activity of contributing to the fulfillment of a need or furtherance of an effort or purpose	a means of serving
the work of providing treatment for or attending to someone or something
a person or thing that is a resource that helps make something easier or possible to do
gift of money or other material help to support a person or cause

aid (verb)	avail (verb)
improve the condition of	take advantage of
give help or assistance; be of service	take or use
	be of use to, be useful to