From The Collaborative International Dictionary of English v.0.48:
Ridge \Ridge\ (r[i^]j), n. [OE. rigge the back, AS. hrycg; akin
to D. rug, G. r["u]cken, OHG. rucki, hrukki, Icel. hryggr,
Sw. rugg, Dan. ryg. [root]16.]
1. The back, or top of the back; a crest. --Hudibras.
[1913 Webster]
2. A range of hills or mountains, or the upper part of such a
range; any extended elevation between valleys. "The frozen
ridges of the Alps." --Shak.
[1913 Webster]
Part rise in crystal wall, or ridge direct.
--Milton.
[1913 Webster]
3. A raised line or strip, as of ground thrown up by a plow
or left between furrows or ditches, or as on the surface
of metal, cloth, or bone, etc.
[1913 Webster]
4. (Arch.) The intersection of two surface forming a salient
angle, especially the angle at the top between the
opposite slopes or sides of a roof or a vault.
[1913 Webster]
5. (Fort.) The highest portion of the glacis proceeding from
the salient angle of the covered way. --Stocqueler.
[1913 Webster]
From The Collaborative International Dictionary of English v.0.48:
Ridge \Ridge\, v. t. [imp. & p. p. Ridged; p. pr. & vb. n.
Ridging.]
1. To form a ridge of; to furnish with a ridge or ridges; to
make into a ridge or ridges.
[1913 Webster]
Bristles ranged like those that ridge the back
Of chafed wild boars. --Milton.
[1913 Webster]
2. To form into ridges with the plow, as land.
[1913 Webster]
3. To wrinkle. "With a forehead ridged." --Cowper.
[1913 Webster]