Webster's Revised Unabridged Dictionary · 1913

Bilberry

Bilberry ({not transcribed}) , noun

[Compare Danish bollebar bilberry, where bolle is perh. akin to English ball.]

1.
(Botany) The European whortleberry (Vaccinium myrtillus); also, its edible bluish black fruit.
There pinch the maids as blue as bilberry. — Shakespeare
2.
(Botany) Any similar plant or its fruit; esp., in America, the species Vaccinium myrtilloides, Vaccinium caspitosum and Vaccinium uliginosum.