vaccinium uliginosum
Webster's Dictionary (GCIDE)
Bilberry \Bil"ber*ry\, n.; pl. Bilberries. [Cf. Dan. b["o]lleb[ae]r bilberry, where b["o]lle is perh. akin to E. ball.]
1.(Bot.) The European whortleberry (Vaccinium myrtillus); also, its edible bluish black fruit. [1913 Webster]
There pinch the maids as blue as bilberry.— Shak.[1913 Webster]
2.(Bot.) Any similar plant or its fruit; esp., in America, the species Vaccinium myrtilloides, Vaccinium c[ae]spitosum and Vaccinium uliginosum. [1913 Webster]