I. ˈme-t ə l-ˌȯid noun
Date: 1813
1. : an element intermediate in properties between the typical metals and nonmetals
2. : a nonmetal that can combine with a metal to form an alloy
II. adjective
also met·al·loi·dal ˌme-t ə l-ˈȯi-d ə l
Date: 1836
1. : resembling a metal
2. : of, relating to, or being a metalloid