Lexic.us

Definition of Selenium

1. Noun. A toxic nonmetallic element related to sulfur and tellurium; occurs in several allotropic forms; a stable grey metallike allotrope conducts electricity better in the light than in the dark and is used in photocells; occurs in sulfide ores (as pyrite).

Definition of Selenium

1. n. A nonmetallic element of the sulphur group, and analogous to sulphur in its compounds. It is found in small quantities with sulphur and some sulphur ores, and obtained in the free state as a dark reddish powder or crystalline mass, or as a dark metallic-looking substance. It exhibits under the action of light a remarkable variation in electric conductivity, and is used in certain electric apparatus. Symbol Se. Atomic weight 78.9.

Definition of Selenium

1. Noun. A nonmetallic chemical element (''symbol'' Se) with an atomic number of 34. ¹

¹ Source: wiktionary.com

Definition of Selenium

1. a nonmetallic element [n -S] : SELENOUS [adj]

Medical Definition of Selenium

1. Essential trace element that must be provided as a supplement in serum free culture media for most animal cells. This entry appears with permission from the Dictionary of Cell and Molecular Biology (11 Mar 2008)

Lexicographical Neighbors of Selenium

Literary usage of Selenium

Below you will find example usage of this term as found in modern and/or classical literature:

1. Standard Methods of Chemical Analysis: A Manual of Analytical Methods and by Wilfred Welday Scott (1917)
"Separation of selenium and Tellurium from Cadmium, Copper and Bismuth. ... 1.175) precipitates selenium and tellurium free from cadmium, and the greater ..."

2. Analytical Chemistry by Frederick Pearson Treadwell (1910)
"Three cases are to be considered: I. The selenium is present as alkali selenite ... The precipitation of selenium by sulphur dioxide is always quantitative ..."

3. Standard Methods of Chemical Analysis: A Manual of Analytical Methods and by Wilfred Welday Scott (1922)
"Weigh as metallic selenium. In order to quickly obtain a constant weight, it is sometimes necessary to break up the precipitate of the selenium in the ..."

4. Encyclopaedia Britannica: A Standard Work of Reference in Art, Literature (1907)
"With metallic selenium, which behaves similarly, the increase of conductivity is proportional to the increase of temperature to near the fusing point (217° ..."

5. A Dictionary of Chemical Solubilities: Inorganic by Arthur Messinger Comey, Dorothy Anna Hahn (1921)
"selenium fluoride. Sol. in cone. HF+Aq. Decomp. immediately by H,O. (Knox. ... selenium nitride. See Nitrogen selenide. selenium monoxide, SeO f?). ..."

6. A Dictionary of Chemistry and the Allied Branches of Other Sciences by Henry Watts (1869)
"Amorphous selenium softens when heated, becomes semifluid at 100°, ... On cooling, the selenium remains soft for a long time, and may be drawn out, ..."

7. Annals of the New York Academy of Sciences by New York Academy of Sciences (1916)
"BIOCHEMICAL STUDIES OF selenium 1 BY VICTOR E. LEVINE (Presented in abstract before the Academy, 18 May, 1914) CONTENTS Page Introduction Sodium selenite as ..."

8. A Treatise on Chemistry by Henry Enfield Roscoe, Harold Govett Colman, Arthur Harden (1903)
"The emission spectrum of selenium is seen when a small bead of the element ... The absorption spectrum of selenium has been examined by Gernez.3 The atomic ..."

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