• WordNet 3.6
    • adj metalloid of or being a nonmetallic element that has some of the properties of metal "arsenic is a metalloid element"
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Webster's Revised Unabridged Dictionary
    • n Metalloid Formerly, the metallic base of a fixed alkali, or alkaline earth; -- applied by Sir Humphrey Davy to sodium, potassium, and some other metallic substances whose metallic character was supposed to be not well defined.
    • Metalloid Having the appearance of a metal.
    • Metalloid (Chem) Having the properties of a nonmetal; nonmetallic; acid; negative.
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Century Dictionary and Cyclopedia
    • metalloid Relating to metalloids; like metal; having the form or appearance of a metal.
    • n metalloid In chem., a term which has been variously applied: as
    • n metalloid to the metallic bases of the fixed alkalis and alkaline earths, probably in consequence of their low specific gravity; and.
    • n metalloid to all the non-metallic elementary substances. In the latter sense it is now used by chemists. The metalloids are thirteen in number: oxygen, hydrogen, nitrogen, carbon, chlorin, bromine, iodine, fluorin, sulphur, seleuium, phosphorus, boron, and silicon. The distinction between a metal and a metalloid is, however, purely artificial, being based on physical rather than chemical criteria : but, broadly, a metal may be said to differ from a metalloid in being an excellent conductor of heat and electricity, in reflecting light more or less powerfully, and in being electropositive. Though a metalloid may possess one or more of these characters, it will not be found to unite them all. Berzelius, in his classification, restricts the term metalloid to the inflammable nonmetallic elements—sulphur, phosphorus, carbon, and boron. See element, 3, and metal, 1.
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Chambers's Twentieth Century Dictionary
    • Metalloid one of the metallic bases of the fixed alkalies and alkaline earths: any of the elements which are non-metallic in the chemical sense of being able to replace hydrogen in an acid, and thus forming a salt: one of the inflammable non-metallic elements (sulphur, phosphorus, &c.)
    • adjs Metalloid pertaining to, or of the nature of, the metalloids
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Webster's Revised Unabridged Dictionary
L. metallum, metal + -oid,: cf. F. métalloïde,
Chambers's Twentieth Century Dictionary
Fr.,—L. metallum—Gr. metallon, a mine, a metal.


In literature:

What is the cause of the absence of metalloids in the Sun?
"The Scientific Basis of National Progress" by George Gore