U.S.A., United States, United States of America, US, USA, America, U.S. - North American republic containing 50 states - 48 conterminous states in North America plus Alaska in northwest North America and the Hawaiian Islands in the Pacific Ocean; achieved independence in 1776

genus Matricaria, Matricaria - chiefly Old World strong-smelling weedy herbs; comprises plants sometimes included in other genera: e.g. Tanacetum; Tripleurospermum

herb, herbaceous plant - a plant lacking a permanent woody stem; many are flowering garden plants or potherbs; some having medicinal properties; some are pests