Definition, Meaning & Synonyms
foid
noun
/fɔɪd/
Definition
A suffix used in the classification of certain rocks and minerals that indicates the presence of specific types of material.
Examples
- Foid-bearing rocks are common in certain volcanic regions.
- The study of foids helps geologists understand magma composition.
- Examples of foid-rich rocks include phonolite and nepheline syenite.
Meaning
In geology, ‘foid’ refers to a group of volcanic or intrusive rocks that are rich in feldspathoids, which are similar to feldspar but have different chemical properties.
Synonyms
- feldspathoid
- alkali feldspar
- nepheline
