[bit-er-root, -roo
t] 
| a plant, Lewisia rediviva, of the purslane family, having pink flowers and fleshy roots that are edible when young: the state flower of Montana. |
| a river in SW Montana, flowing N to the Clark Fork River. 120 mi. (193 km) long. |
| bit·ter·root (bĭt'ər-rōōt', -rŏŏt') n. A perennial herb (Lewisia rediviva) native to western North America and having showy pink or whitish flowers and an edible fleshy root. |
bitterroot
(Lewisia rediviva), ornamental succulent plant of the purslane family (Portulacaceae), native to western North America and cultivated in rock gardens. The main stem and root merge into a tuberous structure. The leaves are barely 2.5 cm (1 inch) long, and the flowering stalk with pink or white flowers is also very short. The starchy root, resembling a forked radish, is edible in spring but acquires a bitter taste by summer. Other species of the genus, which has about 22 species, also are cultivated as rock-garden plants for their attractive flowers
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