The Collaborative International Dictionary of English v.0.48:
Lichen \Li"chen\ (l[imac]"k[e^]n; 277), n. [L., fr. Gr.
leichh`n.]
1. (Bot.) One of a class of cellular, flowerless plants,
(technically called Lichenes), having no distinction of
leaf and stem, usually of scaly, expanded, frond-like
forms, but sometimes erect or pendulous and variously
branched. They derive their nourishment from the air, and
generate by means of spores. The species are very widely
distributed, and form irregular spots or patches, usually
of a greenish or yellowish color, upon rocks, trees, and
various bodies, to which they adhere with great tenacity.
They are often improperly called rock moss or tree
moss.
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Note: A favorite modern theory of lichens (called after its
inventor the Schwendener hypothesis), is that they are
not autonomous plants, but that they consist of
ascigerous fungi, parasitic on alg[ae]. Each lichen is
composed of white filaments and green, or greenish,
rounded cells, and it is argued that the two are of
different nature, the one living at the expense of the
other. See Hyph[ae], and Gonidia.
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2. (Med.) A name given to several varieties of skin disease,
esp. to one characterized by the eruption of small,
conical or flat, reddish pimples, which, if unchecked,
tend to spread and produce great and even fatal
exhaustion.
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The Collaborative International Dictionary of English v.0.48:
Rock \Rock\, n. [OF. roke, F. roche; cf. Armor. roc'h, and AS.
rocc.]
1. A large concreted mass of stony material; a large fixed
stone or crag. See Stone.
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Come one, come all! this rock shall fly
From its firm base as soon as I. --Sir W.
Scott.
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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.
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3. That which resembles a rock in firmness; a defense; a
support; a refuge.
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The Lord is my rock, and my fortress. --2 Sam. xxii.
2.
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4. Fig.: Anything which causes a disaster or wreck resembling
the wreck of a vessel upon a rock.
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5. (Zool.) The striped bass. See under Bass.
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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.
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Rock alum. [Probably so called by confusion with F. roche a
rock.] Same as Roche alum.
Rock barnacle (Zool.), a barnacle (Balanus balanoides)
very abundant on rocks washed by tides.
Rock bass. (Zool.)
(a) The stripped bass. See under Bass.
(b) The goggle-eye.
(c) The cabrilla. Other species are also locally called
rock bass.
Rock builder (Zool.), 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. (Zool.) See Moco.
Rock cod (Zool.)
(a) A small, often reddish or brown, variety of the cod
found about rocks andledges.
(b) A California rockfish.
Rock cook. (Zool.)
(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 (Zool.), any one of several species of large
crabs of the genus C, as the two species of the New
England coast (Cancer irroratus and Cancer borealis).
See Illust. under Cancer.
Rock cress (Bot.), a name of several plants of the cress
kind found on rocks, as Arabis petraea, Arabis lyrata,
etc.
Rock crystal (Min.), limpid quartz. See Quartz, and under
Crystal.
Rock dove (Zool.), 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 (Zool.), the harlequin duck.
Rock eel. (Zool.) See Gunnel.
Rock goat (Zool.), a wild goat, or ibex.
Rock hopper (Zool.), a penguin of the genus Catarractes.
See under Penguin.
Rock kangaroo. (Zool.) See Kangaroo, and Petrogale.
Rock lobster (Zool.), 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 oil. See Petroleum.
Rock parrakeet (Zool.), 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 (Zool.), the wild pigeon (Columba livia) Of
Europe and Asia, from which the domestic pigeon was
derived. See Illust. under Pigeon.
Rock pipit. (Zool.) See the Note under Pipit.
Rock plover. (Zool.)
(a) The black-bellied, or whistling, plover.
(b) The rock snipe.
Rock ptarmigan (Zool.), 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 (Zool.), 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 (Zool.), the harbor seal. See Seal.
Rock shell (Zool.), any species of Murex, Purpura, and
allied genera.
Rock snake (Zool.), any one of several large pythons; as,
the royal rock snake (Python regia) of Africa, and the
rock snake of India (Python molurus). The Australian
rock snakes mostly belong to the allied genus Morelia.
Rock snipe (Zool.), 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. (Zool.)
(a) Any one of several species of Old World sparrows of
the genus Petronia, as Petronia stulla, of Europe.
(b) A North American sparrow (Pucaea ruficeps).
Rock tar, petroleum.
Rock thrush (Zool.), any Old World thrush of the genus
Monticola, or Petrocossyphus; as, the European rock
thrush (Monticola saxatilis), and the blue rock thrush
of India (Monticola 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 (Zool.), any one of several species of marine
food fishes of the genus Hexagrammus, family Chiradae,
native of the North Pacific coasts; -- called also sea
trout, boregat, bodieron, and starling.
Rock warbler (Zool.), a small Australian singing bird
(Origma rubricata) which frequents rocky ravines and
water courses; -- called also cataract bird.
Rock wren (Zool.), any one of several species of wrens of
the genus Salpinctes, native of the arid plains of Lower
California and Mexico.
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