Infusion

1. noun

   a solution obtained by steeping or soaking a substance (usually in water)

   Similar: extract

2. noun

   the process of extracting certain active properties (as a drug from a plant) by steeping or soaking (usually in water)

3. noun

   (medicine) the passive introduction of a substance (a fluid or drug or electrolyte) into a vein or between tissues (as by gravitational force)