petty spurge
/ˈpɛtɪ spəːdʒ/noun
A small annual euphorbia which is often a troublesome weed of cultivated ground, Euphorbia peplus, native to Europe and introduced elsewhere, especially to North America and Australia.
Origin
Late 16th century; earliest use found in Henry Lyte (1529–1607), botanist and antiquary. From petty + spurge.