trench
trench
/trentʃ/
A long, narrow, extremely deep depression in the ocean floor formed by subduction of tectonic plates.
Represents the deepest geographical landforms on Earth, formed where ocean tectonic plates sink under continental plates.
The story behind the word. From Old French trenche, meaning a cut or slice (from verb trancher, to cut). Applied to seafloor geometry when 19th-century hydrographers discovered deep cuts across the ocean floor.
Word relationships
- chasm: A chasm is any deep fissure in rock or earth; a trench in oceanography is specifically a tectonic subduction depression.
- ridge: A mid-ocean ridge is an elevated underwater mountain range formed where plates spread apart.
Commonly confused with
- trough: A trough is a broad, shallow depression; a trench is exceptionally deep and steep-sided.
Word family
- trenched (adjective): Formed into or marked by trenches.
Collocations
- oceanic trench
- deep ocean trench
- subduction trench
- trench floor
Example sentences
- "The Mariana Trench reaches depths of nearly eleven thousand meters in the western Pacific Ocean." Marine geology
Memory hook
TRENCH: like a sharp cut carved deep into the bottom of the sea. Ultra-deep seafloor canyon.
When not to use
Do not use to describe shallow ditches made for home garden drainage unless speaking figuratively.
Fun facts
- If Mount Everest were placed into the Mariana Trench, its peak would still be over 2,000 meters underwater.
Related words
Take your vocabulary further with LangBlitz
Our English vocabulary app: FSRS spaced repetition, 5,000+ curated words across 119 topic groups, CEFR A1 to C2. Explore your mastery with the beautiful Vocabulary World feature.