before vowels mult-, word-forming element meaning "many, many times, much," from combining form of Latin multus "much, many," from PIE *ml-to-, from root *mel- (2) "strong, great, numerous." It was much-used in forming Latin compounds in classical times and after (such as multianimis "having much courage," multibibus "much-drinking," multicomus "having much hair," multiloquus "talkative"). Many English words that use it (multinational, etc.) are 20c. coinages.
late 14c., "having a certain color, having a distinguishing hue," also (c. 1400) "having a certain complexion," past-participle adjective from color (v.). From 1610s as "having a dark or black color of the skin;" specifically, in U.S., "being wholly or partly of African descent," though, as Century Dictionary notes (1897) "In census-tables, etc., the term is often used to include Indians, Chinese, etc."
<a href="https://www.etymonline.com/word/multicolored">Etymology of multicolored by etymonline</a>
Harper, D. (n.d.). Etymology of multicolored. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/multicolored