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mugwort vs. wormwood

mugwort

[muhg-wurt, -wawrt] / ˈmʌgˌwɜrt, -ˌwɔrt /

noun

any of certain weedy composite plants of the genus Artemisia, especially A. vulgaris, having aromatic leaves and small, greenish flower heads.

wormwood

[wurm-wood] / ˈwɜrmˌwʊd /

noun

any composite herb or low shrub of the genus Artemisia.
a bitter, aromatic plant, A. absinthium, of the Old World, used as a vermifuge and a tonic, and as an ingredient in absinthe.
something bitter, grievous, or extremely unpleasant.