Containing its own means of propulsion: a self-propelled golf cart. (adjective)
Fired from or mounted on a moving vehicle: a self-propelled howitzer. (adjective)
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Use "self-propelled" in a sentence
"Once described as "self-propelled flowers", what butterflies do is no less fascinating than the gowns they wear."
"At the same time, seeing the great difficulty with which towed artillery kept up with the armored columns, the Germans began to put more energy into the development of what is nowadays called the self-propelled gun: a medium howitzer mounted on a tank chassis."
"But unlike the Saturn V, the new rocket is intended to carry self-propelled spacecraft that will separate from the rocket after leaving Earth's orbit and continue into deeper space."