catnip or catmint, strong-scented perennial herb (Nepeta cataria) of the family Labiatae (mint family), native to Europe and Asia but naturalized in the United States. A tea of the leaves and flowing tops has long been used as a domestic remedy for various ailments. Catnip is best known for its stimulating effect on cats. Catnip is classified in the division Magnoliophyta, class Magnoliopsida, order Lamiales, family Labiatae.

or catmint

Aromatic herb (Nepeta cataria) of the mint family. Catnip has spikes of small, purple-dotted flowers. It has been used as a seasoning and as a medicinal tea for colds and fever. Because its mintlike flavour and aroma are particularly exciting to domestic cats, it is often used as a stuffing for cat toys.

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