metalloid
An element, such as silicon or germanium, intermediate in properties between that of a metal and a nonmetal; especially an elemental semiconductor.
Other meanings
The metallic base of a fixed alkali, or alkaline earth; applied to sodium, potassium, and some other metallic substances whose metallic character was supposed to be not well defined.
Where this comes from
This definition is adapted from “metalloid” on Wiktionary, by its contributors, published under CC BY-SA 4.0. This page is published under the same licence.