calyx

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. The sepals of a flower considered as a group.
2. n. A cuplike structure or organ, such as one of the cuplike divisions of the pelvis or of the kidney.
3. n. A collecting structure in the kidney.

Century Dictionary and Cyclopedia

1. n. In botany, in general, the outer set of the envelops which form the perianth of a flower. It is usually more herbaceous and leaf-like than the corolla, but it is often highly colored and corolla-like, and is sometimes the first to fall. It may form the entire perianth, no corolla being present; or when there are several whorls of envelops, they may so grade into each other that the calyx cannot be strictly separated from the bracts without and the petals within. The parts of a calyx when distinct are called sepals, and it is disepalous, trisepalous, etc., according to their number. When they are more or less coalescent into a cup or tube, it is said to be gamosepalous or monosepalous, and may be regular or irregular, or variously toothed, cleft, or divided, and either free from the ovary or adnate to it.
2. n. In human anatomy, one of the cup-like or infundibuliform beginnings of the ureter in the pelvis of the kidney, surrounding the apices of the Malpighian pyramids, each receiving usually more than one pyramid. There are from seven to thirteen such calyces, converging and uniting in three infundibula, which in turn combine to form the pelvis. [In this sense calyx is generally found in the plural form, calyces or (incorrectly) calices.]
3. n. In zoology: The cup at the base of the ciliated tentacles on the lophophore or oral disk of polyzoans. See Plumatella.
4. n. The pedicellated Graafian follicle, ovarian capsule, or ovisac of a bird, consisting of two membranes of lax tissue and blood-vessels, rupturing at a point called the stigma to discharge the ovum, then collapsing, and finally becoming absorbed.
5. n. In crinoids, the cup at the summit of the stȧlk or stem, whence the brachia radiate and on the surface of which is the mouth. The base of the calyx is the summit of the stem, which may be a modified joint or ossicle composed of confluent joints. See cut under Crinoidea.
6. n. In Hydrozoa, a generative capsule developed in the axils of a branched hydroid stock, containing either medusa-buds or sexual organs.
7. n. Some other calyciform or cup-shaped part or organ of an animal.
8. n. The expanded, cup-like, deciduous structure on the ends of the stems of certain entoproctous Polyzoa, containing most of the organs and hence practically an individual.
9. n. A depression formed by the more or less reticulate folding of the skin, as in the intromittent organs of snakes.
10. n. A cup-shaped excavation on the surface of the ovary which remains after the rupture of a Graafian vesicle.
11. n. Any circular piece which resembles in form the calyx of a flower.

Wiktionary

1. n. anatomy A cup-like structure in the mammalian kidney.
2. n. botany The outermost whorl of flower parts, comprising the sepals, when it is not the same in appearance as the next such whorl (the corolla).
3. n. zoology The crown of a crinoid.

GNU Webster's 1913

1. n. (Bot.) The covering of a flower. See flower.
2. n. (Anat.) A cuplike division of the pelvis of the kidney, which surrounds one or more of the renal papillæ.

WordNet 3.0

1. n. (botany) the whorl of sepals of a flower collectively forming the outer floral envelope or layer of the perianth enclosing and supporting the developing bud; usually green