yarrowEnglishOxford New American Dictionaryyarrow /ˈyerō, ˈjɛroʊ / ▸ noun a Eurasian plant of the daisy family, with feathery leaves and heads of small white, yellow, or pink aromatic flowers. Also called milfoil. Achillea millefolium, family Compositae. – ORIGIN Old English gearwe, of West Germanic origin; related to Dutch gerwe.