concavity

Trig would take off just as the concavity of one hill was flipping from positive to negative.

The little concavity between the false vocal bands above and the true vocal bands below is termed the ventricle of the larynx.

Then rest the cork with the forks as counter-weights upon the end of the egg to which the concavity has been adapted.

Next cut a slight concavity in one end of one of the corks, so as to adapt it as exactly as possible to one end of an egg.

It drops into a vast concavity in the sand rock, where the water is of unfathomable depth, black and still.

Long shallow flakes were removed to thin the base in the basal concavity.