Bilberry

Merry Wives of Windsor, [5.5.41-45]. Pistol. “Elves, list your names; silence, you airy toys!/ Cricket, to Windsor chimneys shalt thou leap./ Where fires thou find’st unrak’d and hearths unswept/ There pinch the maids as blue as bilberry./ Our radiant Queen hates sluts and sluttery.”

*
a sort of blueberry.