To pour in, as a liquid; to pour (into or upon); to shed.

To steep in water or other fluid without boiling, for the propose of extracting medicinal qualities; to soak.

To brew in hot water or other liquids to extract flavor.

To steep in a liquid in order to extract juices. The resulting drink is called an 'infusion'.

To instill, as principles or qualities; to introduce.

introduce into the body through a vein, for therapeutic purposes; "Some physiologists infuses sugar solutions into the veins of animals"

To introduce a solution into the body through a vein.

To inject a substance directly into the veins.