[Hail, Mary! ] [Ave, 2 syl.). The first two words of the angel's salutation to the Virgin Mary. (Luke i. 28.) In the Roman Catholic Church the phrase is applied to an invocation to the Virgin beginning with those words; and also to the smaller beads of a rosary, the larger ones being termed pater-nosters.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894