unrevealing

It submerged at once, and went due south at twelve knots an hour below the unrevealing seas.

The straight, hard lines of her lean figure were a complement to her gleaming, unrevealing eyes.

There are darker stories, too, of deeds whose secret was known only to the hidden tunnel and unrevealing waters below.

Baffled for the moment, he was silent, watching her unrevealing face.

The face of the American Indian is said to be unrevealing—to be a stoic mask under which his emotions are ever hidden.