Also found in: Dictionary, Thesaurus, Medical, Legal, Financial, Acronyms, Encyclopedia, Wikipedia.
Related to reaction: reaction time
A series of events wherein the outcome of each instance specifically influences or causes the next. The phrase comes from the occurrence of such reactions in chemistry and physics. Deciding to take a course studying James Joyce in college set up a chain reaction that ultimately led me to move to Ireland. When one bookshelf fell, it caused a chain reaction that knocked over all the rest.
A reaction to a situation based on a person's instinct and feelings, rather than on a logical analysis. My initial gut reaction was that the merger would result in a drop in stock prices, but the opposite turned out to be true.
Fig. an automatic or reflex reaction; an immediate reaction made without examining causes or facts. With one of his typical knee-jerk reactions, he said no immediately, citing some moral argument that no one understood.
See also: reaction
a gut reaction
a reaction that is based on your immediate feelings about someone or something When a tragedy like this happens, I think people's gut reaction is anger and a desire to find someone to blame.See bust a gut, bust a gut
A series of events in which each influences or gives rise to the next event, as in If one person collects substantial damages by suing a company, you can expect a chain reaction of such lawsuits . The term originated in the physical sciences, first (1920s) chemistry and later (1940) physics; in the latter it denotes a process of nuclear fission. By the 1940s it had been transferred to more general use.
gut reaction (to something)
n. a basic and immediate response to something. Her gut reaction to the plan is basically a good one.