an abundant nonmetallic tetravalent element occurring in three allotropic forms: amorphous carbon and graphite and diamond; occurs in all organic compounds
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"
operating with minimal human intervention; independent of external control; "automatic transmission"; "a budget deficit that caused automatic spending cuts"
like the unthinking functioning of a machine; "an automatic `thank you'"; "machinelike efficiency"
without volition or conscious control; "the automatic shrinking of the pupils of the eye in strong light"; "a reflex knee jerk"; "sneezing is reflexive"