shell

(redirected from shells)
Also found in: Dictionary, Thesaurus, Legal, Idioms, Encyclopedia.
Related to shells: Electron shells

shell

(shel),
An outer covering.

shell

Etymology: AS, scell
1 a hard outer protective covering that encloses material.
2 a principal energy level occupied by an electron in an atom.

shell

(shel)
An outer covering.

shell

any hard outer covering, such as the carapace of turtles and tortoises, the exoskeleton of crustaceans, the calcareous plates of echinoderms, the outermost membranes of an egg, the skeleton of Foraminifera or the mantle secretions of molluscs.

impression, eye

A negative form or replica of the anterior part of the eye. A substance with rapid gelling properties is held in contact with the eye until gelled. This impression (or mould) is then used in the preparation of a positive model called a cast (or casting) of the anterior part of the eye: it is made by filling the impression with a material containing a plaster of Paris base which hardens to artificial stone. Using this cast a shell of a scleral contact lens is produced with optimum shape of the back surface. Syn. impression; impression moulding; mould; ocular impression.
References in classic literature ?
I have often wondered since why he should have carried about these shells with him in his wandering, guilty, and hunted life.
Their next business is from herbs, minerals, gums, oils, shells, salts, juices, seaweed, excrements, barks of trees, serpents, toads, frogs, spiders, dead men's flesh and bones, birds, beasts, and fishes, to form a composition, for smell and taste, the most abominable, nauseous, and detestable, they can possibly contrive, which the stomach immediately rejects with loathing, and this they call a vomit; or else, from the same store-house, with some other poisonous additions, they command us to take in at the orifice above or below (just as the physician then happens to be disposed) a medicine equally annoying and disgustful to the bowels; which, relaxing the belly, drives down all before it; and this they call a purge, or a clyster.
The wooden bedstead, the waxed mahogany chairs, the chest of drawers, those brasses, the little square antimacassars carefully placed on the backs of the chairs, the clock on the mantelpiece and the harmless-looking ebony caskets at either end, lastly, the whatnot filled with shells, with red pin-cushions, with mother-of-pearl boats and an enormous ostrich-egg, the whole discreetly lighted by a shaded lamp standing on a small round table: this collection of ugly, peaceable, reasonable furniture, AT THE BOTTOM OF THE OPERA CELLARS, bewildered the imagination more than all the late fantastic happenings.
Not only did the chevalier have his own particular shells, but he cherished an ambitious desire which he pursued with a craft so profound as to be worthy of Sixtus the Fifth: he wanted to marry a certain rich old maid, with the intention, no doubt, of making her a stepping-stone by which to reach the more elevated regions of the court.
I had seen that the eggs were in the process of hatching, and as I stood watching the hideous little monsters break from their shells I failed to note the approach of a score of full-grown Martians from behind me.
So he commenced to bargain, and in the end the person of Meriem passed from the possession of the black chieftain into that of the two Swedes in consideration of six yards of Amerikan, three empty brass cartridge shells and a shiny, new jack knife from New Jersey.
With the passionate song of the bullets and the banshee shrieks of shells were mingled loud catcalls and bits of facetious advice concerning places of safety.
After a whole day spent in this employment, he would return about nightfall with several cocoanut shells filled with different descriptions of kelp.
They were clean, nice oyster shells, large, and just like any other oyster shells.
From in front and especially from the right, in the unlifting smoke the guns boomed, and out of the mysterious domain of smoke that overlay the whole space in front, quick hissing cannon balls and slow whistling shells flew unceasingly.
We got some shells yesterday dropped within a quarter of a mile of us.
As the dropping shells burst nearer and nearer, what final self-control he possessed left him.