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Related to reaction: reaction time

chain reaction

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.
See also: chain, reaction

gut reaction

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.
See also: gut, reaction

gut reaction to (something)

A reaction to a situation based on a person's instinct and feelings, rather than on a logical analysis. My initial gut reaction to news of the merger was that it would result in a drop in stock prices, but the opposite turned out to be true.
See also: gut, reaction, to

knee-jerk reaction

Any spontaneous, reflexive, and unthinking reaction or response. I know my knee-jerk reaction to the film's ending was mostly negative, but over time I've come to appreciate its subtlety and poignancy. Unsurprisingly, there has been a knee-jerk reaction from many parents to have the book banned from schools.
See also: reaction

my reaction when

slang A phrase used primarily in online communications alongside images of humorous facial expressions to indicate a person's typical reaction to something. She replied to my SpaceBook post with, "My reaction when people post pictures of their vacation" above a picture of a snoring child. It was a bit rude, but I couldn't help but laugh.
See also: reaction
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

knee-jerk reaction

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
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.

chain reaction

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.
See also: chain, reaction
The American Heritage® Dictionary of Idioms by Christine Ammer. Copyright © 2003, 1997 by The Christine Ammer 1992 Trust. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

a gut reaction

COMMON A gut reaction is a reaction that you have immediately and strongly, without thinking about something or being aware of your reasons. At first my gut reaction was to never write again. My heart's loyal to the party but my gut reaction is to vote against the bill.
1. If you describe a task or activity as gut-busting, you mean it is very hard work. It would be hard work, he predicted — back-breaking, gut-busting, unbelievably hard work.
2. You can use gut-busting to describe a very large amount of food. Walker set a record by eating a gut-busting 32 pies.
See also: gut, reaction
Collins COBUILD Idioms Dictionary, 3rd ed. © HarperCollins Publishers 2012

gut reaction (to something)

n. a basic and immediate response to something. Her gut reaction to the plan is basically a good one.
See also: gut, reaction, something, to

gut reaction

See also: gut, reaction
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions Copyright © 2006 by The McGraw-Hill Companies, Inc. All rights reserved.
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References in periodicals archive ?
Just over 11 percent (134) of the reactions were categorized as severe, and included symptoms such as swelling in the throat, difficulty breathing, a sudden drop in blood pressure, dizziness or fainting.
In all the groups, allergic skin reactions or pseudoallergic skin reactions were noted using causality assessment.
The purpose of this study was to look for significant differences in the mean scores between 5th grade boys and girls in simple reaction time, one and two choice reaction times.
Reaction optimization becomes even more critical as processes are scaled up for further testing, characterization and manufacturing of the compound of interest, but this is where technology has, to date, lagged behind.
The PGL-1 antigen stimulates the formation of IgM anti-PGL-1 antibody, which reacts with newly formed PGL-1 antigen and causes an ENL reaction.8 Acute symptoms found in ENL are suspected to indicate the increasing natural excessive immune function, reflected by an increase in TNF-[alpha], TGF-[beta] and antibody IgM anti-PGL-1.
Without a history of the previous allergic reaction after being stung, positive skin test, and/or venom-specific IgE are not enough to give the diagnosis.
In 2002, Bojan Zalar, Martina Tomori and Ivan Krajnc conducted a study that measured the simple reaction rate in patients with schizophrenia before and after treatment with antipsychotics.
In the comparison of the reaction time between the groups of male and female, the choice reaction time of male athletes were found shorter than female athletes and the difference was statistically significant (p<0.01).
- Can other drugs administered simultaneously also be responsible of the reaction?
From these data, it can be concluded that a traumatic venepuncture, compared to an easy one, is a strong determinant of a vasovagal reaction. It can, therefore, be stated that a painful stimulus caused by venepuncture can lead to a vasovagal reaction.
Indoor concentration, distribution, and residence time are main aspects to describe the characteristics of both reactants and reaction products.
The reactions are meant to make it easier and more fun for women on the app to call out rude or disrespectful behavior.
The company will roll out 'reactions' instead of a much requested dislike button which will include 'love', 'haha', 'yay', 'wow', 'sad' and 'angry', each of which has a corresponding picture.
Green chemistry; environmentally benign reactions, 2d ed.