serving or used to introduce; preliminary; beginning: an introductory course; an introductory paragraph.
Origin of introductory
Synonyms for introductory
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
serving as an introduction; preliminary; prefatory
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
c.1600, from Late Latin introductorius, from introduct-, past participle stem of introducere "to lead in, bring in" (see introduction). Also used in English from c.1400 as a noun meaning "introductory treatise or textbook."
Online Etymology Dictionary, © 2010 Douglas Harper