4x4 Definition
fôrbīfôr
4x4s
noun
A four-wheel-drive vehicle.
Webster's New World
abbreviation
A piece of timber with a cross section of 4 inches square.
Wiktionary
(automotive) A four-wheel-drive vehicle with a four-speed transmission.
Wiktionary
(automotive) A four-wheel vehicle with four-wheel-drive.
Wiktionary
(automotive) By extension, any four-wheel-drive vehicle.
Wiktionary