Echinoidea
(||Ech`i*noi"de*a) n. pl. [NL. See Echinus, and -oid.] (Zoöl.) The class Echinodermata
which includes the sea urchins. They have a calcareous shell, usually more or less spheroidal or disk-
shaped, composed of many united plates, and covered with movable spines. See Spatangoid, Clypeastroid.
[Written also Echinidea, and Echinoida.]
Echinozoa
(||E*chi`no*zo"a) n. pl. [NL., fr. Gr. 'echi^nos an echinus + zw^,on an animal.] (Zoöl.) The
Echinodermata.
Echinulate
(E*chin"u*late) a. (Bot. & Zoöl.) Set with small spines or prickles.
Echinus
(||E*chi"nus) n.; pl. Echini [L., a hedgehog, sea urchin, Gr. 'echi^nos.]
1. (Zoöl.) A hedgehog.
2. (Zoöl.) A genus of echinoderms, including the common edible sea urchin of Europe.
3. (Arch.) (a) The rounded molding forming the bell of the capital of the Grecian Doric style, which
is of a peculiar elastic curve. See Entablature. (b) The quarter-round molding (ovolo) of the Roman
Doric style. See Illust. of Column (c) A name sometimes given to the egg and anchor or egg and dart
molding, because that ornament is often identified with the Roman Doric capital. The name probably
alludes to the shape of the shell of the sea urchin.
Echiuroidea
(||Ech`i*u*roi"de*a) n. pl. [NL., fr. echiurus, the name of one genus (Gr. 'e`chis an adder
+ o'yra` tail) + -oid.] (Zoöl.) A division of Annelida which includes the genus Echiurus and allies. They
are often classed among the Gephyrea, and called the armed Gephyreans.
Echo
(Ech"o) n.; pl. Echoes [L. echo, Gr. 'hchw` echo, sound, akin to 'hchh`, 'h^chos, sound, noise; cf.
Skr. vaç to sound, bellow; perh. akin to E. voice: cf. F. écho.]
1. A sound reflected from an opposing surface and repeated to the ear of a listener; repercussion of
sound; repetition of a sound.
The babbling echo mocks the hounds.
Shak.
The woods shall answer, and the echo ring.
Pope. 2. Fig.: Sympathetic recognition; response; answer.
Fame is the echo of actions, resounding them.
Fuller.
Many kind, and sincere speeches found an echo in his heart.
R. L. Stevenson. 3. (a) (Myth. & Poetic) A wood or mountain nymph, regarded as repeating, and causing the reverberation
of them.
Sweet Echo, sweetest nymph, that liv'st unseen
Within thy airy shell.
Milton. (b) (Gr. Myth.) A nymph, the daughter of Air and Earth, who, for love of Narcissus, pined away until
nothing was left of her but her voice.
Compelled me to awake the courteous Echo
To give me answer from her mossy couch.
Milton. Echo organ (Mus.), a set organ pipes inclosed in a box so as to produce a soft, distant effect; — generally
superseded by the swell. — Echo stop (Mus.), a stop upon a harpsichord contrived for producing the
