Source : WordNet®

propellent
     adj : tending to or capable of propelling; "propellant fuel for
           submarines"; "the faster a jet plane goes the greater
           its propulsive efficiency"; "universities...the seats
           of propulsive thought" [syn: {propellant}, {propelling},
            {propulsive}]
     n : something that propels [syn: {propellant}]