Never leave the concave side of the soup spoon facing down.
He reached inside his tunic and turned the concave side inward.
Then, with infinite patience, he turned it until the concave side was facing his chest.
The burn marks were on the concave side, the interior.
The concave side often looks like a bite was taken out of it.
Then, as an experiment, he turned the thought mirror so that its concave side faced inward.
The basement rooms received new, concave sides and the floor heights were changed.
It was a curved, 12 cm long knife with the edge on its concave side.
Hold a flour-dusted fork, concave side up, in one hand.
The three officers turned and hurried up the concave side of the amphitheater design.