Calyx \Ca"lyx\, n.; pl. E. Calyxes, L. Calyces. [L. calyx, -ycis, fr. Gr. ? husk, shell, calyx, from the root of ? to cover, conceal. Cf. Chalice Helmet.]

1. (Bot.) The covering of a flower. See Flower.

Note: The calyx is usually green and foliaceous, but becomes delicate and petaloid in such flowers as the anemone and the four-o'clock. Each leaf of the calyx is called a sepal.

2. (Anat.) A cuplike division of the pelvis of the kidney, which surrounds one or more of the renal papill[ae].

Source: Webster's Revised Unabridged Dictionary (1913)