in·fu·sion / inˈfyoōzhən/ • n. 1. a drink, remedy, or extract prepared by soaking the leaves of a plant or herb in liquid. ∎  the process of preparing such a drink, remedy, or extract.2. the introduction of a new element or quality into something: the infusion of $6.3 million for improvements | an infusion of youthful talent. ∎  Med. the slow injection of a substance into a vein or tissue.

infusion (in-few-zhŏn) n.
1. the slow injection of a substance, usually into a vein (intravenous i., IVI). This is a common method for replacing water, electrolytes, and blood products and is also used for the continuous administration of drugs or nutrition. See also drip.

2. the process whereby the active principles are extracted from plant material by steeping it in boiling water (as in the making of tea).

3. the solution produced by this process.