ˈ ̷ ̷ˌ ̷ ̷ noun
1. : a coarse prickly weed ( Echium vulgare ) of Europe that has been naturalized in the United States and that has blue flowers in scorpioid spikes — called also blue devil, blue thistle, viper's bugloss
2. : chicory
3. in Texas : a Mexican weed ( Larrea densiflora ) introduced as a range plant for alkali soils
4. : a small perennial ( Helianthus ciliaris ) that is native in southwestern United States and often troublesome as a weed and that has blue-green or gray-green foliage