[dee-puh n]

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.

Origin of deepen

First recorded in 1595–1605; deep + -en1
Related formsdeep·en·er, noundeep·en·ing·ly, adverbo·ver·deep·en, verb (used with object)un·deep·ened, adjective Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for deepen

Contemporary Examples of deepen

Historical Examples of deepen

  • And a second and a third month may only deepen the sense of ignorance and unfitness.

  • Somehow this fact did not tend to deepen Sears Kendrick's affection for them.

    Fair Harbor

    Joseph Crosby Lincoln

  • Her face was very grave and the lines about her mouth seemed to deepen.

    Keziah Coffin

    Joseph C. Lincoln

  • Bishop's great face seemed to swell and its high colour to deepen.

    Captain Blood

    Rafael Sabatini

  • The enthusiasm of all around only served to increase and deepen my depression.

British Dictionary definitions for deepen



to make or become deep, deeper, or more intense
Derived Formsdeepener, noun
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

Word Origin and History for deepen

c.1600, from deep (adj.) + -en (1). Related: Deepened; deepening. The earlier verb had been simply deep, from Old English diepan.

Online Etymology Dictionary, © 2010 Douglas Harper