early 15c., "convey or bring (something) in or into," a back-formation from introduction or else from Latin introducere "to lead in, bring in," from intro- "inward, to the inside" (see intro-) + ducere "to lead" (from PIE root *deuk- "to lead").
Meaning "to bring forward, open to notice" (of a subject, etc.) is from 1550s. Sense of "bring into personal acquaintance, make known" (as of one person to another) is from 1650s. Related: Introduced; introducing.
<a href="https://www.etymonline.com/word/introducer">Etymology of introducer by etymonline</a>
Harper, D. (n.d.). Etymology of introducer. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/introducer