metalloid

/ˌmɛdlˈɔɪd/

Other forms: metalloids

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.

Definitions of metalloid

1. noun

   a nonmetallic element that has some of the properties of metal
   type of:

   chemical element, element

   any of the more than 100 known substances (of which 92 occur naturally) that cannot be separated into simpler substances and that singly or in combination constitute all matter
2. adjective

   of or being a nonmetallic element that has some of the properties of metal
   “arsenic is a metalloid element”

   synonyms:

   nonmetal, nonmetallic

   not containing or resembling or characteristic of a metal