Synonyms for Bluebell (same or very similar meaning)
WordNet sense 1 (one of the most handsome prairie wildflowers having large erect bell-shaped bluish flowers; of moist places in prairies and fields from eastern Colorado and Nebraska south to New Mexico and Texas):
prairie gentian, Eustoma grandiflorum, tulip gentian
WordNet sense 2 (perennial of northern hemisphere with slender stems and bell-shaped blue flowers):
harebell, Campanula rotundifolia
WordNet sense 3 (sometimes placed in genus Scilla):
wild hyacinth, Hyacinthoides nonscripta, Scilla nonscripta, wood hyacinth
From the ODE community, based on WordNet
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