barmaid n.

"tavern," 1590s, so called in reference to the bars of the barrier or counter over which drinks or food were served to customers (see bar (n.1)).

c. 1200 (late 12c. in place names and surnames), "an unmarried woman (usually young); the Virgin Mary;" shortening of maiden (n.). Like that word, used in Middle English of unmarried men as well as women (as in maiden-man, c. 1200, which was used of both sexes, reflecting also the generic use of man).

From c. 1300 as "a virgin," also as "maidservant, female attendant, lady in waiting." By c. 1500 this had yielded the humbler sense of "female servant or attendant charged with domestic duties." Often with a qualifying word (housemaid, chambermaid, etc.); maid of all work "female servant who performs general housework" is by 1790.

Her Mamma was a famous Fryer of Fishes,

Squeezer of Mops, Washer of Dishes,

From tossing of Pancakes would not Shirk,

In English plain, a Maid of all Work.

But don't mistake me, by Divinity,

When I mention Maid, I don't mean Virginity 

[from "Countess of Fame and her Trumpeter," 1793]

In reference to Joan of Arc, attested from 1540s (French la Pucelle). Maid Marian, the Queen of the May in the morris dances, also one of Robin Hood's companions, is recorded by 1520s, perhaps from French, where Robin et Marian have been stock names for country lovers since 13c. Maid of Honor (1580s) originally was "unmarried lady of noble birth who attends a queen or princess;" meaning "principal bridesmaid" is attested from 1895. Maydelond (translating Latin terra feminarum) was "the land of the Amazons."