To transform (a landscape) on another planet into one having the characteristics of landscapes on Earth. (verb-transitive)
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 "terraform" in a sentence
"Why don't we 'terraform' the Sahara desert before Mars?"
"The Mars Society says that the Earth is a rotting, dying, stinking planet and that we must move our civilization to Mars and that Congress must appropriate funds to "terraform" Mars."
"Personally, I think it is easier, cheaper, and ultimately much more profitable to "terraform" asteroids and comets by hollowing them out and spinning them for gravity."