to throw in; to dart in; to force in; as, to inject cold water into a condenser; to inject a medicinal liquid into a cavity of the body; to inject morphine with a hypodermic syringe.-fig.: to throw; to offer; to propose; to instill.-to cast or throw; -- with on.-to fill (a vessel, cavity, or tissue) with a fluid or other substance; as, to inject the blood vessels.