Definition of "revetment"

Findlayson, C. E., sat in his trolley on a construction line that ran along one of the main revetments—the huge stone-faced banks that flared away north and south for three miles on either side of the river and permitted himself to think of the end.

1898, Rudyard Kipling, “The Bridge-Builders”, in The Day's Work

A 200-ton rockfall recently blocked the Machynlleth sidings, trapping several locomotives; a rock-slip on the approach embankment to Talerddig required expensive revetting last year; and on the coastal section to Barmouth an 80 foot-high stone revetment was completed some time ago at Friog; [...].

1964 December, Mark Bourne, “The rejuvenation of the Cambrian line”, in Modern Railways, page 390