Introductory music such as a prelude or the first movement in a suite of traditional Chinese music

(bound form) A medicinal catalyst or adjuvant used to enhance the effectiveness of a main medicine; an extra ingredient added to a herbal prescription.

(Taiwan) A short strand of DNA or RNA that serves as a starting point for DNA synthesis.

The opening section of a novel or an actor's opening lines upon entering the stage

Remarks made to introduce a topic or inspire others to speak; a lead-in to a discussion

The beginning, cause, or triggering factor of a series of events; an excuse or pretext used to start something