vegetation of tropical mountainous regions where rainfall is often heavy and persistent condensation occurs because of cooling of moisture-laden air currents deflected upward by the mountains —synonym montane rainforests —note trees in a cloud forest are typically short and crooked; mosses, climbing ferns, lichens, and epiphytes form thick blankets on the trunks and branches of the trees; begonias, ferns, and other herbaceous plants may grow exceptionally large in clearings This definition last updated 07/28/2008