What is "test tube"

Test \Test\, n. [OE. test test, or cupel, potsherd, F. t[^e]t, from L. testum an earthen vessel; akin to testa a piece of burned clay, an earthen pot, a potsherd, perhaps for tersta, and akin to torrere to patch, terra earth (cf. Thirst, and Terrace), but cf. Zend tasta cup. Cf. Test a shell, Testaceous, Tester a covering, a coin, Testy, T[^e]te-[`a]-t[^e]te.]

1. (Metal.) A cupel or cupelling hearth in which precious metals are melted for trial and refinement.

   Our ingots, tests, and many mo.
   --Chaucer.

2. Examination or trial by the cupel; hence, any critical examination or decisive trial; as, to put a man's assertions to a test. ``Bring me to the test.''
   --Shak.

3. Means of trial; as, absence is a test of love.

   Each test every light her muse will bear.
   --Dryden.

4. That with which anything is compared for proof of its genuineness; a touchstone; a standard.

   Life, force, and beauty must to all impart, At once the source, and end, and test of art.
   --Pope.

5. Discriminative characteristic; standard of judgment; ground of admission or exclusion.

   Our test excludes your tribe from benefit.
   --Dryden.

6. Judgment; distinction; discrimination.

   Who would excel, when few can make a test Betwixt indifferent writing and the best?
   --Dryden.

7. (Chem.) A reaction employed to recognize or distinguish any particular substance or constituent of a compound, as the production of some characteristic precipitate; also, the reagent employed to produce such reaction; thus, the ordinary test for sulphuric acid is the production of a white insoluble precipitate of barium sulphate by means of some soluble barium salt.

8. A set of questions to be answered or problems to be solved, used as a means to measure a person's knowledge, aptitude, skill, intelligence, etc.; in school settings, synonymous with examination or exam; as, an intelligence test. Also used attributively; as a test score, test results. Test act (Eng. Law), an act of the English Parliament prescribing a form of oath and declaration against transubstantiation, which all officers, civil and military, were formerly obliged to take within six months after their admission to office. They were obliged also to receive the sacrament according to the usage of the Church of England. --Blackstone. Test object (Optics), an object which tests the power or quality of a microscope or telescope, by requiring a certain degree of excellence in the instrument to determine its existence or its peculiar texture or markings. Test paper.

   1. (Chem.) Paper prepared for use in testing for certain substances by being saturated with a reagent which changes color in some specific way when acted upon by those substances; thus, litmus paper is turned red by acids, and blue by alkalies, turmeric paper is turned brown by alkalies, etc.

   2. (Law) An instrument admitted as a standard or comparison of handwriting in those jurisdictions in which comparison of hands is permitted as a mode of proving handwriting. Test tube. (Chem.)

      1. A simple tube of thin glass, closed at one end, for heating solutions and for performing ordinary reactions.

      2. A graduated tube.

         Syn: Criterion; standard; experience; proof; experiment; trial.

         Usage: Test, Trial. Trial is the wider term; test is a searching and decisive trial. It is derived from the Latin testa (earthen pot), which term was early applied to the fining pot, or crucible, in which metals are melted for trial and refinement. Hence the peculiar force of the word, as indicating a trial or criterion of the most decisive kind.

         I leave him to your gracious acceptance, whose trial shall better publish his commediation.
         --Shak.

         Thy virtue, prince, has stood the test of fortune, Like purest gold, that tortured in the furnace, Comes out more bright, and brings forth all its weight.
         --Addison.

a. 1 produced in a test tube 2 conceived or developed in vitro by artificial insemination alt. (context chemistry English) a glass tube, rounded at one end and open at the other; used for small-scale laboratory tests n. (context chemistry English) a glass tube, rounded at one end and open at the other; used for small-scale laboratory tests

n. glass tube closed at one end

A test tube, also known as a culture tube or sample tube, is a common piece of laboratory glassware consisting of a finger-like length of glass or clear plastic tubing, open at the top, usually with a rounded U-shaped bottom.

A large test tube specifically for boiling liquids is called a boiling tube.

Test tubes are available in a multitude of lengths and widths, typically from 10 to 20 mm wide and 50 to 200 mm long. The top often features a flared lip to aid pouring out the contents; some sources consider that the presence of a lip is what distinguishes a test tube from a culture tube. A test tube has either a flat bottom, a round bottom, or a conical bottom. Some test tubes are made to accept a ground glass stopper or a screw cap. They are often provided with a small ground glass or white glaze area near the top for labelling with a pencil.