verb
deepen
DEE-puhn
verb
1
To make or become deeper.
"Years of erosion deepened the canyon."
"The river deepens sharply past the old bridge."
2
To make or become more intense, serious, or extreme.
"Their friendship deepened after they survived the crisis together."
"The recession deepened as more factories closed."
3
To make or become darker in colour, or lower in tone or pitch.
"The sky deepened to purple as the sun went down."
"His voice deepened noticeably during puberty."
How to Use Deepen
Learner’s notesIn plain EnglishTo get deeper, more intense, or more serious — used for holes, colours, sounds, feelings, and situations alike.
Common pairings
deepen a crisis
deepen a relationship
the shadows deepened
Word Forms
deepened past tense, deepens singular
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Years of erosion _____ the canyon.
Etymology
From deep + the verb-forming suffix -en, the same pattern seen in "widen" and "harden."