Reactive intermediate is a term used in chemistry to describe unstable molecules or ions that are formed during a chemical reaction and quickly reacted further to form more stable products. There are several synonyms used for reactive intermediate that includes transient species, reaction intermediates, and reactive species. Other synonyms include the term short-lived intermediates, which refer to the temporary existence of such intermediates in the reaction pathway. Additionally, highly reactive species is another synonym used for reactive intermediates, as these species tend to readily undergo further reactions. These synonyms help to convey the properties and characteristics of reactive intermediates in a concise and clear manner.