Any ornamental summer-blooming plant of the genus Coreopsis, commonly known as tickseed, in the composite family, consisting of about 100 species of annual and perennial herbaceous plants native to North America. Members have flower heads with yellow disk flowers and yellow, pink, white, or variegated ray flowers. The heads are solitary or in branched clusters, and some varieties have double flowers. Golden coreopsis (C. tinctoria) is a popular garden plant; swamp tickseed (C. rosea) is grown in wildflower gardens.

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