Ca"lyx (kā"l&ibreve;ks; 277), n.; pl. E. Calyxes (#), L. Calyces (kăl"&ibreve;*sēz). [L. calyx, -ycis, fr. Gr. ka`lyx husk, shell, calyx, from the root of kaly`ptein to cover, conceal. Cf. Chalice Helmet.] 1. (Bot.) The covering of a flower. See Flower.

&fist; 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 papillæ.

• (botany) Collective term for the sepals of a flower, i.e. the outermost whorl of flower parts, when this is not the same in appearance as the next such whorl (the corolla).
  
• A cup-like structure in the kidney