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steepen

American  
[stee-puhn] / ˈsti pən /

verb (used with or without object)

  1. to make or become steeper. steep.

steepen British  
/ ˈstiːpən /

verb

  1. to become or cause to become steep or steeper

"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

Etymology

Origin of steepen

First recorded in 1840–50; steep 1 + -en 1

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

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.