What does "serrate" mean?

Serrate: (Bot.) Beset with teeth pointing forwards or upwards; as, serrate leaves. Doubly serrate, having small serratures upon the large ones, as the leaves of the elm. -- Serrate-ciliate, having fine hairs, like the eyelashes, on the serratures; -- said of a leaf. -- Serrate-dentate, having the serratures toothed.