1. Any of several Old World coarse prickly-leaved shrubs and subshrubs having milky juice and yellow flowers; widely naturalized; often noxious weeds in cultivated soil
   "Farmers struggled to control the spread of sow thistle in their fields";
   - milk thistle

Derived forms: sow thistles

Type of: bush, shrub

Part of: genus Sonchus, Sonchus

Encyclopedia: Sow thistle