Here's why:
* "Opaque" is a descriptor, not a specific type. Opaque watercolor simply means watercolor that is not transparent. It covers the surface completely, hiding the underlying paper or paint.
* "Gouache" is often mistaken as a synonym, but it's different. Gouache is a type of watercolor paint that is formulated to be opaque. However, you can also achieve opacity in regular watercolor by using techniques like layering, using white gouache, or adding a white pigment like Titanium White.
So, while there isn't a single, universally recognized alternative term for "opaque watercolor," you could use phrases like:
* "Body color watercolor"
* "Opaque watercolor paint"
* "Gouache-like watercolor" (if referring to a particular brand or technique)
Ultimately, the best way to describe it is to use the term "opaque watercolor" or explain what makes it opaque (e.g., "this is a watercolor paint that is opaque because it contains white pigment").