The definition of avail is to help or give an advantage.(verb)
An example of avail is for medication to improve the condition of a sick person.
See avail in Webster's New World College Dictionary
intransitive verb, transitive verb
Origin: ME availen < OFr a (L ad), to + valoir, to be worth < L valere, to be strong: see value
See avail in American Heritage Dictionary 4
verb a·vailed, a·vail·ing, a·vails verb, transitive
Origin: Middle English availen
Origin: : a-, intensive pref. (from Latin ad-; see ad-)
Origin: + Old French valoir, vail-, to be worth (from Latin valēre, to be strong; see wal- in Indo-European roots).
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