twin1

[twin] /twɪn/
noun
1.
either of two children or animals brought forth at a birth.
2.
either of two persons or things closely related to or closely resembling each other.
3.
twin bed.
4.
Also called twin room. a type of hotel accommodation with twin beds, for occupancy by two persons.
Compare double (def 13).
5.
Also called hemitrope. Crystallography. a compound crystal consisting of two or more parts or crystals definitely oriented each to the other; macle.
6.
Twins, Astronomy, Astrology. the constellation or sign of Gemini.
adjective
7.
being a twin or twins:
twin sisters.
8.
being two persons or things closely related to or closely resembling each other.
9.
being one of a pair; identical:
a twin bracelet; a twin peak.
10.
consisting of two similar parts or elements joined or connected:
a twin vase.
11.
Botany, Zoology. occurring in pairs; didymous.
12.
Crystallography. of the nature of a twin; hemitrope.
13.
twofold or double.
verb (used with object), twinned, twinning.
14.
to bring together in close relationship; pair; couple.
15.
to furnish a counterpart to or a replica of; match.
16.
Informal. to divide or convert into two, parts, similar items, etc.:
The old movie palace will be twinned, making two smaller theaters.
17.
Informal. to link or combine with:
The new grocery store is twinned with a restaurant.
18.
Crystallography. to form into a twin.
19.
Obsolete. to give birth to as twins.
verb (used without object), twinned, twinning.
20.
to give birth to twins.
21.
to be paired or coupled.
Origin
before 900; Middle English; Old English twinn (adj.), getwinn (noun and adj.); akin to Old Frisian twīne, Old Norse tvinnr double, Gothic twaihnai

twin2

[twin] /twɪn/
verb (used with object), verb (used without object), twinned, twinning. Scot.
1.
twine2 .
Examples from the web for twin
  • While no record remains of what happened to her twin or her other brother.
  • In addition to routinely rejecting a twin, panda moms have been known to ignore single cubs.
  • It also terrifies my cats and my three-year-old twin boys.
  • But alongside these twin pillars of food news stand a host of other developments and trends.
  • Christine made her entrance after he'd tossed the last suitcase onto the brown metal twin.
  • The study sought to determine how likely the second twin was to have some form of autism.
  • The twin concerns are inflation and the current-account deficit.
  • From twin tanks filled by servants, a steady flow of water was cupped and spilled by a series of buckets mounted on a wheel.
  • Cheap oil might merely aggravate the twin evils of corruption and bad government.
  • Each twin of a pair played the ultimatum game, both as proposer and as responder.
British Dictionary definitions for twin

twin

/twɪn/
noun
1.
  1. either of two persons or animals conceived at the same time
  2. (as modifier): a twin brother See also identical (sense 3), fraternal (sense 3)
2.
  1. either of two persons or things that are identical or very similar; counterpart
  2. (as modifier): twin carburettors
3.
Also called macle. a crystal consisting of two parts each of which has a definite orientation to the other
verb twins, twinning, twinned
4.
to pair or be paired together; couple
5.
(intransitive) to bear twins
6.
(intransitive) (of a crystal) to form into a twin
7.
(intransitive) (archaic) to be born as a twin
8.
(transitive)
  1. to create a reciprocal relation between (two towns in different countries); pair (a town) with another in a different country
  2. (intransitive) (of a town) to be paired with a town in a different country
Derived Forms
twinning, noun
Word Origin
Old English twinn; related to Old High German zwiniling twin, Old Norse tvinnr double
Word Origin and History for twin
adj.

Old English twinn "consisting of two, twofold, double," probably ultimately from Proto-Germanic *twinjaz (cf. Old Norse tvinnr, Old Danish tvinling, Dutch tweeling, German zwillung), from PIE *dwisno- (cf. Latin bini "two each," Lithuanian dvynu "twins"), from *dwi- "double," from root *dwo- "two" (see two). The verb meaning "to combine two things closely" is recorded from late 14c. The noun developed from Old English getwinn "double."

twin in Medicine

twin (twĭn)
n.
One of two offspring born at the same birth. adj.

  1. Being two or one of two offspring born at the same birth.

  2. Consisting of two identical or similar parts; double.

twin in Science
twin
  (twĭn)   

  1. One of two offspring born of a single gestation. Identical twins result from the division of a fertilized egg. Fraternal twins result from the fertilization of two separate eggs at the same time.

  2. A crystal structure consisting of two intergrown crystals that are mirror images of each other. Mineral twins can form as result of defective crystal growth in response to stress from rock deformation or during magma cooling.


Encyclopedia Article for twin

either of two young who are simultaneously born from one mother. Twinning, common in many animals, is of two biological kinds: the one-egg (monozygotic), or identical, type and the two-egg (dizygotic), or fraternal, type. The latter type is more usual and can be thought of simply as a litter of two. In humans, psychological studies of sets of identical twins, since they are genetically identical, have provided much otherwise unobtainable information on the relative effects of genetic endowment and environment. See also multiple birth.

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