Under the Whyte notation system, a duplex steam locomotive that has four leading wheels in a leading truck, two sets of four driving wheels, and a four-wheel trailing truck.

Under the Whyte notation system, a steam locomotive that has four leading wheels arranged in a leading truck, four coupled driving wheels and four trailing wheels in a trailing truck.

(music) A meter of four quarter notes per measure.

(text messaging, slang) abbreviation of for

(military) Skyhawk single engine attack aircraft. / (military) Air material and supply officer. / (military) Material and supply section of an Air Force staff.

plural of 4-4-4-4

Under the Whyte notation system, a duplex steam locomotive that has four leading wheels in a leading truck followed by four coupled driving wheels, a second set with six coupled driving wheels, and four trailing wheels in a trailing truck.

Under the Whyte notation system, a duplex steam locomotive that has four leading wheels in a leading truck followed by six coupled driving wheels, a second set with four coupled driving wheels, and four trailing wheels in a trailing truck.

Under the Whyte notation system, a Garratt steam locomotive that is articulated in three parts, with a boiler mounted on the centre frame, and two steam engines mounted in opposite directions on separate frames, one on each end of the boiler, and each engine having a 4-8-4 wheel configuration.

plural of 4-4-2