steepening

1. gerundparticiplepresentPresent participle and gerund of steepen.

   1 more example

   All three parallel valleys of the Llynvi, Garw and Ogmore are much the same in physical character: the lower reaches are wooded and not unattractive, but as the railway climbs on ever-steepening grades, the hills on either hand grow barer and closer together, while in all respects the scene becomes more sombre, with the terraced, slate-roofed colliery towns and the road, railway and river all struggling for space in the narrowing defiles.

   1955 July, D. S. Barrie, “Railways of the Bridgend District”, in Railway Magazine, page 449

plural steepenings

1. The process of becoming steeper.