hummock

The thought seemed to produce the dreaded object, for next moment a large hummock appeared right ahead.

We had to cross what is called a hummock, which was in reality a depression, but not low enough to be swampy.

Hair-Face ran out on the quaking morass and gained the firmer footing of a grass-hummock a dozen yards away.

A hummock is a protuberance raised upon any plane of ice above the common level.

And then, when we had cautiously rounded a hummock at the top, my steel helmet was blown off—not by a shrapnel, but by the wind!