Synonyms

deepen

American

[dee-puhn] / ˈdi pən /

verb (used with or without object)

to make or become deep or deeper.

Larger ships will be able to navigate the river after the main channel is deepened. The shadows deepened toward late afternoon.
Meteorology. to decrease in atmospheric pressure.

a deepening cyclone.

deepen British

/ ˈdiːpən /

verb

to make or become deep, deeper, or more intense

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

Derived Forms

Conjugated Forms

Present

Past

Future

Etymology

Origin of deepen

First recorded in 1595–1605; deep + -en ¹

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

In London, the eclipse will begin at 03:33 BST and deepen until maximum eclipse at 05:12 BST, when around 90% of the Moon will be immersed in Earth's umbra, the darkest part of its shadow.

From BBC • Jun. 6, 2026

Espriella has promised to deepen US-Colombian relations "like never before" if elected.

From Barron's • Jun. 5, 2026

The funding will help Mach Industries expand its manufacturing, advance its technology and deepen its partnerships with customers that include the U.S.

From Los Angeles Times • Jun. 3, 2026

O’Donnell, 42 years old, isn’t pitching Canary as a replacement for humans but as a force multiplier, allowing analysts to cover additional stocks or to deepen their understanding of the ones on their watchlists.

From The Wall Street Journal • May 31, 2026

With a stick the Raven Leader stirred the fire, and Torak saw the lines of pain deepen on either side of his mouth.

From "Wolf Brother" by Michelle Paver

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023