rainforest

UK: /ˈreɪnfɒrɪst/

Collins Concise English Dictionary © HarperCollins Publishers::

rainforest / ˈreɪnˌfɒrɪst/ noun

1. dense forest found in tropical areas of heavy rainfall. The trees are broad-leaved and evergreen, and the vegetation tends to grow in three layers (undergrowth, intermediate trees and shrubs, and very tall trees, which form a canopy)

WordReference Random House Learner's Dictionary of American English © 2026

ˈrain ˌfor•est or ˈrainˌfor•est, n. [countable]

1. Ecology a tropical forest, usually of tall, densely growing, broad-leaved, evergreen trees in an area where much rainfall occurs.

WordReference Random House Unabridged Dictionary of American English © 2026

rain′ for′est, 

1. Ecology a tropical forest, usually of tall, densely growing, broad-leaved evergreen trees in an area of high annual rainfall.

Also, rain′for′est. 

• 1900–05