The fronds of tree ferns are usually very large and multiple-pinnated, but at least one type has entire (undivided) fronds. The fronds of tree ferns also exhibit circinate vernation, meaning the young fronds emerge in coils that uncurl as they grow.he order Cyatheales, which includes the tree ferns, is a taxonomic division of the fern class, Polypodiopsida.
rap noun (MUSIC) A2 [ U ] a type of popular music with a strong rhythm in which the words are spoken, not sung:
Rap music is part of Hip-Hop culture. Although rap music is often referred to a hip-hop, there is no style of music simply called hip-hop. There is hip-hop music, and the name for it is rap. Repeat one more time: Rap = music. Hip-hop = culture.