noun (n)

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

  Synonym:
  extract
  

  source: wordnet30
• the process of extracting certain active properties (as a drug from a plant) by steeping or soaking (usually in water)(noun.process)

  source: wordnet30
• (medicine) the passive introduction of a substance (a fluid or drug or electrolyte) into a vein or between tissues (as by gravitational force)(noun.act)

  source: wordnet30
• the act of infusing or introducing a certain modifying element or quality(noun.act)

  Example:
  The team's continued success is attributable to a steady infusion of new talent.
  

  source: wordnet30
• The act of infusing, pouring in, or instilling; instillation; as, the infusion of good principles into the mind; the infusion of ardor or zeal.(noun)

  source: webster1913