IPA: /ˌdiːfɔːrɪˈsteɪʃən/
KK: /dɪˌfɔrɪˈsteɪʃən/
The act of cutting down trees in a forest to use the land for something else, like farming or building.
Deforestation is a major environmental issue that affects wildlife and climate.
Deforestation is formed from "de-" (meaning down or away) and "forest" (from Latin "foresta", meaning woodland or forest) and "-ation" (a suffix indicating an action or process). The word describes the process of removing or clearing away forests.
Think of 'removing' ('de-') 'woodland' ('forest') — that's what deforestation means.