There was a monotone of desolation as she went on speaking in a whisper meant for the ears of no other.

The inexorable voice went on in its monotone, as if he had not spoken.

Then her voice rose above the monotone that had contented her hitherto.

"Her husband caused it by kicking her in the stomach," she said in a monotone.

The voice was a monotone, minus expression, almost minus life.

The driver was shouting to them in a monotone, "Now, there, my dears."

His monotone, ended abruptly, resumed after a vast interval.

Has it not come to you that I might wish to study and that monotone is anything but pleasant?

The monotone of the wind and the monochrome of the sky oppress him.

A monotone is a single tone without harmony or variation in pitch.