metalloid

American  

[met-l-oid] / ˈmɛt lˌɔɪd /

noun

1. a nonmetal that in combination with a metal forms an alloy.

2. an element that has both metallic and nonmetallic properties, as arsenic, silicon, or boron.

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adjective

1. of or relating to a metalloid.

2. resembling both a metal and a nonmetal.

metalloid British  

/ ˈmɛtəˌlɔɪd /

noun

1. a nonmetallic element, such as arsenic or silicon, that has some of the properties of a metal

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adjective

1. of or being a metalloid

2. resembling a metal

metalloid Scientific  

/ mĕt′l-oid′ /

1. An element that is not a metal but that has some properties of metals. Arsenic, for example, is a metalloid that has the visual appearance of a metal, but is a poor conductor of electricity; metalloids are generally semiconductors. The elements classified as metalloids are boron, silicon, germanium, arsenic, antimony, tellurium, and polonium. Metalloids can be viewed as a diagonal section on the Period Table, separating metals from nonmetals.

2. A nonmetallic element, such as carbon, that can form alloys with metals.

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Etymology

Origin of metalloid

First recorded in 1825–35; metall- + -oid

Explanation

In chemistry, an element that isn't metal, but has many things in common with metal, is known as a metalloid. Silicon and arsenic are examples of metalloids. As far as scientific terms go, metalloid is not very precise. It's a general category for elements whose properties put them somewhere in between a metal and a nonmetal — they share characteristics of both. Scientists disagree over both the definition of metalloid and which elements can be described this way, though there are six on which most chemists concur: boron, silicon, germanium, arsenic, antimony, and tellurium.

Example Sentences

Arsenic, a highly toxic element that resembles a metal but which is technically a metalloid, was an easily accessible poison in the mid-19th century; its poisonous properties were widely known.

From Salon • Mar. 5, 2023

"Arsenic is a metalloid that is present in all parts of the environment," Labay told Salon.

From Salon • Mar. 5, 2023

The metalloid boron exhibits many similarities to its neighbor carbon and its diagonal neighbor silicon.

From Textbooks • Feb. 14, 2019

A metalloid is an element that has properties that are between those of metals and nonmetals; these elements are typically semiconductors.

From Textbooks • Feb. 14, 2019

It contains no garnet or amphibole, but metalloid diallage disseminated in the mass.

From Personal Narrative of Travels to the Equinoctial Regions of America, During the Year 1799-1804 — Volume 3 by Humboldt, Alexander von