Granitoid

Part of speech: adjective

Definitions

1. A rock type characterized by a coarse-grained texture and a mineral composition that resembles granite, typically containing quartz, feldspar, and mica
2. Denoting a geological formation that has a granitic texture and is primarily composed of minerals like quartz, feldspar, and mica
3. A rock characterized by a granitic texture that commonly consists of minerals such as quartz, feldspar, and mica is referred to in this context

Etymology: Granitoid is a plain compound: "granite" with the suffix "-oid", from Greek "eidos", meaning "form" or "resemblance." Put together, it means "resembling granite." The suffix is the familiar one found in words like "android" (resembling a man) and "asteroid" (star-like), so the word is essentially a description of a rock that has granite's look and texture without necessarily being granite itself. That distinction is the useful part. Geologists use "granitoid" as a broad umbrella for coarse-grained, crystalline igneous rocks that share granite's mineral makeup, typically quartz, feldspar, and mica, even when the exact proportions differ. The word thus lets a field geologist describe a rock confidently before the lab has settled on a precise classification.

Synonyms: granite-like