4 × 4
or four-by-four
[ fawr bahy fawr, fohr bahy fohr, buh ]
/ ˈfɔr baɪ ˌfɔr, ˈfoʊr baɪ ˌfoʊr, bə /
noun
a four-wheeled automotive vehicle having four-wheel drive.
a piece of lumber approximately 4 inches thick by 4 inches wide.