Closeup of Euphorbia plantImage Source
Euphorbia is a genus of flowering plants belonging to the family Euphorbiaceae. Consisting of 2008 species, Euphorbia is the fourth largest genus of flowering plants; it also has one of the largest ranges of chromosome counts, along with Rumex and Senecio. Members of the family and genus are commonly referred to as spurges.
The common name "spurge" derives from the Middle English/Old French espurge ("to purge"), due to the use of the plant's sap as a purgative. Spurge often presents itself as a noxious weed, harmful to lawns and gardens. Source