| Noun | 1. | Amsonia - genus of herbs and subshrubs with milky juice and showy bluish flowers; Europe to Asia Minor to Japan and North America dicot genus, magnoliopsid genus - genus of flowering plants having two cotyledons (embryonic leaves) in the seed which usually appear at germination Apocynaceae, dogbane family, family Apocynaceae - chiefly tropical trees or shrubs or herbs having milky juice and often showy flowers; many are sources of drugs Amsonia tabernaemontana, blue star - subshrubs of southeastern United States forming slow-growing clumps and having blue flowers in short terminal cymes |