steepen

[ stee-puh n ]

/ ˈsti pən /

to make or become steeper.

Origin of steepen

First recorded in 1840–50; steep¹ + -en¹

The side walls were steepened and precipitous cirques were formed at the valley heads.

The Andes of Southern Peru |Isaiah Bowman
If by chance the detritus accumulates rapidly, the slope is steepened and the work of the torrent made more efficient.

Outlines of the Earth's History |Nathaniel Southgate Shaler
The grade has ever steepened, till now it is forty degrees or more.

The Columbia River |William Denison Lyman
Meanwhile the sides of the valley head are steepened and driven back to precipitous walls.

The Elements of Geology |William Harmon Norton

The slope had now steepened considerably, and further conversation died out in the effort of climbing.

The Image and the Likeness |John Scott Campbell

steepen

/ (ˈstiːpən) /

to become or cause to become steep or steeper