Sad Clotho held the rocke, the whiles the thread By
grisly Lachesis was spun with pain, That cruel Atropos
eftsoon undid. --Spenser.
Come one, come all! this rock shall fly From its
firm base as soon as I. --Sir W.
Scott.
2. (Geol.) Any natural deposit forming a part of the earth's
crust, whether consolidated or not, including sand, earth,
clay, etc., when in natural beds.
3. That which resembles a rock in firmness; a defense; a
support; a refuge.
The Lord is my rock, and my fortress. --2 Sam. xxii.
2.
4. Fig.: Anything which causes a disaster or wreck resembling
the wreck of a vessel upon a rock.
5. (Zo["o]l.) The striped bass. See under {Bass}.
Note: This word is frequently used in the formation of
self-explaining compounds; as, rock-bound, rock-built,
rock-ribbed, rock-roofed, and the like.
{Rock alum}. [Probably so called by confusion with F. roche a
rock.] Same as {Roche alum}.
{Rock barnacle} (Zo["o]l.), a barnacle ({Balanus balanoides})
very abundant on rocks washed by tides.
{Rock bass}. (Zo["o]l.)
(a) The stripped bass. See under {Bass}.
(b) The goggle-eye.
(c) The cabrilla. Other species are also locally called
rock bass.
{Rock builder} (Zo["o]l.), any species of animal whose
remains contribute to the formation of rocks, especially
the corals and Foraminifera.
{Rock butter} (Min.), native alum mixed with clay and oxide
of iron, usually in soft masses of a yellowish white
color, occuring in cavities and fissures in argillaceous
slate.
{Rock candy}, a form of candy consisting of crystals of pure
sugar which are very hard, whence the name.
{Rock cavy}. (Zo["o]l.) See {Moco}.
{Rock cod} (Zo["o]l.)
(a) A small, often reddish or brown, variety of the cod
found about rocks andledges.
(b) A California rockfish.
{Rock cook}. (Zo["o]l.)
(a) A European wrasse ({Centrolabrus exoletus}).
(b) A rockling.
{Rock cork} (Min.), a variety of asbestus the fibers of which
are loosely interlaced. It resembles cork in its texture.
{Rock crab} (Zo["o]l.), any one of several species of large
crabs of the genus {Cancer}, as the two species of the New
England coast ({C. irroratus} and {C. borealis}). See
Illust. under {Cancer}.
{Rock cress} (Bot.), a name of several plants of the cress
kind found on rocks, as {Arabis petr[ae]a}, {A. lyrata},
etc.
{Rock crystal} (Min.), limpid quartz. See {Quartz}, and under
{Crystal}.
{Rock dove} (Zo["o]l.), the rock pigeon; -- called also {rock
doo}.
{Rock drill}, an implement for drilling holes in rock; esp.,
a machine impelled by steam or compressed air, for
drilling holes for blasting, etc.
{Rock duck} (Zo["o]l.), the harlequin duck.
{Rock eel}. (Zo["o]l.) See {Gunnel}.
{Rock goat} (Zo["o]l.), a wild goat, or ibex.
{Rock hopper} (Zo["o]l.), a penguin of the genus
{Catarractes}. See under {Penguin}.
{Rock kangaroo}. (Zo["o]l.) See {Kangaroo}, and {Petrogale}.
{Rock lobster} (Zo["o]l.), any one of several species of
large spinose lobsters of the genera {Panulirus} and
{Palinurus}. They have no large claws. Called also {spiny
lobster}, and {sea crayfish}.
{Rock meal} (Min.), a light powdery variety of calcite
occuring as an efflorescence.
{Rock milk}. (Min.) See {Agaric mineral}, under {Agaric}.
{Rock moss}, a kind of lichen; the cudbear. See {Cudbear}.
{Rock parrakeet} (Zo["o]l.), a small Australian parrakeet
({Euphema petrophila}), which nests in holes among the
rocks of high cliffs. Its general color is yellowish olive
green; a frontal band and the outer edge of the wing
quills are deep blue, and the central tail feathers bluish
green.
{Rock pigeon} (Zo["o]l.), the wild pigeon ({Columba livia})
Of Europe and Asia, from which the domestic pigeon was
derived. See Illust. under {Pigeon}.
{Rock pipit}. (Zo["o]l.) See the Note under {Pipit}.
{Rock plover}. (Zo["o]l.)
(a) The black-bellied, or whistling, plover.
(b) The rock snipe.
{Rock ptarmigan} (Zo["o]l.), an arctic American ptarmigan
({Lagopus rupestris}), which in winter is white, with the
tail and lores black. In summer the males are grayish
brown, coarsely vermiculated with black, and have black
patches on the back.
{Rock rabbit} (Zo["o]l.), the hyrax. See {Cony}, and {Daman}.
{Rock ruby} (Min.), a fine reddish variety of garnet.
{Rock salt} (Min.), cloride of sodium (common salt) occuring
in rocklike masses in mines; mineral salt; salt dug from
the earth. In the United States this name is sometimes
given to salt in large crystals, formed by evaporation
from sea water in large basins or cavities.
{Rock seal} (Zo["o]l.), the harbor seal. See {Seal}.
{Rock shell} (Zo["o]l.), any species of Murex, Purpura, and
allied genera.
{Rock snake} (Zo["o]l.), any one of several large pythons;
as, the royal rock snake ({Python regia}) of Africa, and
the rock snake of India ({P. molurus}). The Australian
rock snakes mostly belong to the allied genus {Morelia}.
{Rock snipe} (Zo["o]l.), the purple sandpiper ({Tringa
maritima}); -- called also {rock bird}, {rock plover},
{winter snipe}.
{Rock soap} (Min.), a kind of clay having a smooth, greasy
feel, and adhering to the tongue.
{Rock sparrow}. (Zo["o]l.)
(a) Any one of several species of Old World sparrows of
the genus {Petronia}, as {P. stulla}, of Europe.
(b) A North American sparrow ({Puc[ae]a ruficeps}).
{Rock thrush} (Zo["o]l.), any Old World thrush of the genus
{Monticola}, or {Petrocossyphus}; as, the European rock
thrush ({M. saxatilis}), and the blue rock thrush of India
({M. cyaneus}), in which the male is blue throughout.
{Rock tripe} (Bot.), a kind of lichen ({Umbilicaria
Dillenii}) growing on rocks in the northen parts of
America, and forming broad, flat, coriaceous, dark fuscous
or blackish expansions. It has been used as food in cases
of extremity.
{Rock trout} (Zo["o]l.), any one of several species of marine
food fishes of the genus {Hexagrammus}, family
{Chirad[ae]}, native of the North Pacific coasts; --
called also {sea trout}, {boregat}, {bodieron}, and
{starling}.
{Rock warbler} (Zo["o]l.), a small Australian singing bird
({Origma rubricata}) which frequents rocky ravines and
water courses; -- called also {cataract bird}.
{Rock wren} (Zo["o]l.), any one of several species of wrens
of the genus {Salpinctes}, native of the arid plains of
Lower California and Mexico.
The rocking town Supplants their footsteps. --J.
Philips .
2. To roll or saway backward and forward upon a support; as,
to rock in a rocking-chair.
A rising earthquake rocked the ground. --Dryden.
2. To move as in a cradle; hence, to put to sleep by rocking;
to still; to quiet. ``Sleep rock thy brain.'' --Shak.
Note: Rock differs from shake, as denoting a slower, less
violent, and more uniform motion, or larger movements.
It differs from swing, which expresses a vibratory
motion of something suspended.