deepen

American  

[dee-puhn] / ˈdi pən /

verb (used with or without object)

1. 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.

2. Meteorology. to decrease in atmospheric pressure.

   a deepening cyclone.

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deepen British  

/ ˈdiːpən /

verb

1. to make or become deep, deeper, or more intense

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Other Word Forms

• deepener
  noun
• deepeningly
  adverb
• overdeepen
  verb (used with object)
• undeepened
  adjective

Etymology

Origin of deepen

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

Example Sentences

Across Substack, Instagram and IRL gatherings, it brings together fragrance lovers and newcomers eager to deepen their understanding in an interactive way.

From Los Angeles Times • May 19, 2026

Older children, usually from seven upwards, can feel isolated or "quite jealous" of peers who haven't experienced loss, and grief can deepen as understanding grows, Sadie added.

From BBC • May 16, 2026

Modi's visit will "deepen India's partnership with Europe... particularly trade and investment ties in light of the recently concluded India-EU FTA", New Delhi's foreign ministry said.

From Barron's • May 15, 2026

"In order to accelerate the research and development of quantum technologies, it is crucial to deepen our understanding of basic concepts to come up with innovative ideas," says Takeuchi.

From Science Daily • May 13, 2026

As the cinder town began to deepen, cooling to mere scarlet, Ralph began to discern the familiar road again — to reassure himself that they were indeed on an ordinary highway with other cars.

From "Typical American" by Gish Jen

Related Words

• aggravate
• develop
• enhance
• expand
• heighten
• increase
• intensify
• redouble
• reinforce
• strengthen