shell / shel/ • n. 1. the hard protective outer case of a mollusk or crustacean: cowrie shells| the technique of carving shell. ∎  the thin outer covering of an animal's egg, which is hard and fragile in that of a bird but leathery in that of a reptile. ∎  the outer case of a nut kernel or seed. ∎  the carapace of a tortoise, turtle, or terrapin. ∎  the wing cases of a beetle. ∎  the integument of an insect pupa or chrysalis. ∎  (one's shell) fig. used with reference to a state of shyness or introversion: she'll soon come out of her shell with the right encouragement.2. something resembling or likened to a shell because of its shape or its function as an outer case: pasta shells baked pastry shells filled with cheese. ∎  the walls of an unfinished or gutted building or other structure: the hotel was a shell, the roof having collapsed completely. ∎ fig. an outer form without substance: he was a shell of the man he had been previously. ∎  a light racing boat used in the sport of crew. ∎  a woman's sleeveless sweater or blouse. ∎  the metal framework of a vehicle body. ∎  an inner or roughly made coffin. ∎  the handguard of a sword. ∎  Physics each of a set of orbitals around the nucleus of an atom, occupied or able to be occupied by electrons of similar energies.3. an explosive artillery projectile or bomb: the sound of the shell passing over, followed by the explosion | [as adj.] shell holes. ∎  a hollow metal or paper case used as a container for fireworks, explosives, or cartridges. ∎  a cartridge.4. Comput. short for shell program.• v. 1. [tr.] bombard with shells: the guns started shelling their positions.2. [tr.] remove the shell or pod from (a nut or seed): they were shelling peas | [as adj.] (shelled) shelled Brazil nuts. 3. [intr.] gather seashells: there was nothing to do except swim or go shelling on the beaches.PHRASAL VERBS: shell something out (or shell out) inf. pay a specified amount of money, esp. an amount that is resented as being excessive: it doesn't make sense to shell out $8.50 for an elevator ride.DERIVATIVES: shelled adj. [in comb.] : a soft-shelled clam. shell-less adj.shell-like / -ˌlīk/ adj.shell·y / ˈshelē/ adj.

shell.
1. Concrete structure evolved from work by Candela, Freyssinet, Maillart, Nervi, Nowicki, Saarinen, and Torroja, and derived from the exemplar of an eggshell. The stressed skin or shell operates with the frame to form a strong structural system.

2. Scallop.

3. Ornament called coquillage in which shells and mother-of-pearl pieces are used for effect in grottoes, marine ornament, nymphaea, etc.

Bibliography

J. Joedicke (1963);
Lewis & Darley (1986);
W. Papworth (1887)

shell A program that provides the user interface of an operating system and is often considered to be part of it. The main inner part of the operating system, the kernel, is thus enclosed by the shell, as in a nut. Some operating systems have a choice of shells.

shell hard outer covering of an animal, fruit, etc.; scale or scale-like object OE.; hollow or concave object XVI; exterior cover or case (spec. one containing powder and shot) XVII. OE. (Angl.) sċell, (WS.) sċiell = (M)LG., MDu. schelle, schille, Du. schel, schil pod, rind, scale, shell, ON. skel sea-shell, Goth. skalja tile :- Gmc. *skaljō, f. *skal- (cf. SCALE1, 2).
Hence vb. XVI.

shell In biology, the hard protective case of various molluscs. or eggs of animals, such as birds, tortoises, turtles, or snakes. The case is secreted by the epidermis of the mollusc and consists of a protein matrix strengthened by calcium carbonate. The shell of a bird is also mostly composed of calcium.