adjective. Using the air from the atmosphere for combustion

adjective. Which can breathe air for a short period of time; especially the airbreathing catfishes.

"For SSTO to become real and to make sense, we need high energy-density propellants to minimize the structural mass fraction and do it without all kinds of airbreathing claptrap that has to operate in a truly rotten environment and yet be "easily" maintained."

airbrushing