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Any hard calcareous or chitinous organ found in the mouth of various invertebrates and used in feeding or procuring food; as, the teeth of a mollusk or a starfish. In spite of the teeth, in defiance of opposition; in opposition to every effort. -- In the teeth, directly; in direct opposition; in front. "Nor strive wit…

In an inverted posture; with the top or head downward; upside down; as, to turn a carriage topsy-turvy.

To change; to transform; to invert. [R.] Things base and vile, holding no quantity, Love can transpose to form and dignity. Shak.

A pit in the form of an inverted cone or pyramid, constructed as an obstacle to the approach of an enemy, and having a pointed stake in the middle. The pits are called also trapholes.

A grand division of the animal kingdom, intermediate, in some respects, between the invertebrates and vertebrates, and by some writers united with the latter. They were formerly classed with acephalous mollusks. The body is usually covered with a firm external tunic, consisting in part of cellulose, and having two open…

Shaped like a top, or inverted cone; narrow at the base, and broad at the apex; as, a turbinated ovary, pericarp, or root.

To invert a type of the same thickness, as temporary substitute for any sort which is exhausted. To turn about, to face to another quarter; to turn around. -- To turn again, to come back after going; to return. Shak. -- To turn against, to become unfriendly or hostile to. -- To turn aside or away. (a) To turn from t…

A thermometer by merely inverting which the temperature may be registered. The column of mercury is broken and, as it remains until the instrument is reset, the reading may be made at leisure.

ng, a system of organs which eliminate nitrogenous waste matter from the blood of certain invertebrates.

A receptacle, or pouch, connected with the oviducts of many invertebrates in which the eggs are retained until they hatch or until the embryos develop more or less. See Illust. of Hermaphrodite in Append.

The terminal part of the oviduct in insects and various other invertebrates. See Illust., of Spermatheca.

ater vascular system (Zoöl.), a system of vessels in annelids, nemerteans, and many other invertebrates, containing a circulating fluid analogous to blood, but not of the same composition. In annelids the fluid which they contain is usually red, but in some it is green, in others yellow, or whitish.…

The anal opening of certain invertebrates and fishes; also, the external cloacal opening of reptiles, birds, amphibians, and many fishes.

The orifice of the oviduct of an insect or other invertebrate.

, or head, shaped like the top of a covered wagon, or resembling in section or outline an inverted U, thus as, a wagonheaded ceiling.

Having a roof, or top, shaped like an inverted U; wagon-headed.

A pore by which the water tubes of various invertebrates open externally.

One of a system of tubular excretory organs having external openings, found in many invertebrates. They are believed to be analogous in function to the kidneys of vertebrates. See Illust. under Trematodea, and Sporocyst.

pintail. (b) The old squaw. -- Winter egg (Zoöl.), an egg produced in the autumn by many invertebrates, and destined to survive the winter. Such eggs usually differ from the summer eggs in having a thicker shell, and often in being enveloped in a protective case. They sometimes develop in a manner different from that…

pecial organ which secretes the yolk of the eggs in many turbellarians, and in some other invertebrates. See Illust. of Hermaphrodite in Appendix. -- Yolk sack (Anat.), the umbilical vesicle. See under Unbilical.