More about gouache
Gouache, “an opaque watercolor prepared with gum,” is a loanword from French and is adapted from Italian guazzo, originally meaning “place where there is water.” Guazzo, in turn, apparently comes from Latin aquātiō, of the same meaning, from aqua, “water.” The Italian descendant of Latin aqua is acqua, and the Latin suffix -tiō usually becomes -gione, -zione, or -zzone in Italian, which is why Latin aquātiō is also the source of Italian acquazzone, “downpour.” How guazzo came into being, when it does not follow standard Latin-to-Italian sound change patterns, is a bit of a mystery, but one possibility is that guazzo reflects an early borrowing from a Romance language of northern Italy. Gouache was first recorded in English in the early 1880s.
EXAMPLE OF GOUACHE USED IN A SENTENCE
In contrast to watercolors, which are designed to be translucent, the thickness of gouache allows for bold colors after a single session of painting.