| Noun | 1. | Eustoma - small genus of herbs of warm regions of southern North America to northern South America dicot genus, magnoliopsid genus - genus of flowering plants having two cotyledons (embryonic leaves) in the seed which usually appear at germination family Gentianaceae, gentian family, Gentianaceae - chiefly herbaceous plants with showy flowers; some are cultivated as ornamentals Eustoma grandiflorum, prairie gentian, tulip gentian, bluebell - 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 |