Englishfor English speakers
concave
Adjective
—
If the surface of something is concave, it is curved like the inner surface of a sphere or bowl.
vein
Noun
—
A vein is a tube in the body that carries blood back to the heart.
—
A vein is a bump or line in a leaf where sap flows.
—
A vein is a fissure, cleft, or cavity in the earth.