It tended to travel down the center of the track, swinging to and fro with slight vertical undulations".

A slight undulation of the waves carried it farther under the low arch of the crypt, and there Ayrton, with the aid of flint and steel, lighted the lamp.

Now that they were above it, they could see slight undulations in the semi-transparent fog.

Here is distinguished slight undulations and uneven elevations formed by continuous alluvial actions, of nature or of man.

The relief of the land in the municipality is irregular but smooth, with slight undulations.

It can also be intended (inaccurately) to refer to vibrato, which is a slight undulation in pitch.

Only the slightest undulation of the land is noticeable.

In this range, the water surface shows slight undulations and because of this, jumps in this range are sometimes known as undular jumps.

She was looking back along the procession of the caravan now, and she could see the other machines rising and falling in waves as they moved over slight undulations in the trail.

This Chine is difficult to identify as there is no obvious stream valley leading to the cliff edge, just a slight undulation of the gently sloping agricultural land.