A compound adjective is a single adjective comprising more
than one word. The words in a compound adjective are usually grouped
together using hyphens.
Compound adjectives can also be grouped using italics, quotation marks and
title case (i.e., capital letters). This is covered more in the lesson Alternatives
to Hyphens in Compound Adjectives.
Interactive example:
He took the beach-surfing
buggy on a 4-week training camp. [show
me the compound adjectives]