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:
The 25 Best Rappers 25 And Under. The 25 Best Rappers 25 And Under. Rap is a young man's game. Hip-hop has always been consumed and created by young people. It's that youthful exuberance that leads the culture into exciting new directions.