[ sahy-kol-uh-jee ]
/ saɪˈkɒl ə dʒi /
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noun, plural psy·chol·o·gies.
the science of the mind or of mental states and processes.
the science of human and animal behavior.
the sum or characteristics of the mental states and processes of a person or class of persons, or of the mental states and processes involved in a field of activity: the psychology of a soldier; the psychology of politics.
mental ploys or strategy: He used psychology on his parents to get a larger allowance.
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Origin of psychology

From the New Latin word psȳchologia, dating back to 1675–85. See psycho-, -logy


pre·psy·chol·o·gy, noun


psychiatry, psychology , psychoanalysis, psychotherapy
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023


What does psych mean?

Psych is an informal term with several meanings.

Psych means to intimidate or scare someone mentally and is usually followed by out, as in Shareen psyched me out about trying out for the play by telling me the director didn’t like actors.

Psych also means to prepare yourself or someone else mentally to give their best and is usually followed by up, as in Yana psyched up her team by reminding them of all their previous wins. To psych up usually involves preparing mentally, rehearsing skills or responses, and thinking positive thoughts.

Psych also means to decipher or analyse situations and problems to come to a solution and is often followed by out, as in After a lot of work, Lana finally psyched out the math problem. When you psyche out a problem, it means you have or are in the process of finding a solution through complex thought.

Example: The mascot tried to psych out the other team by dancing wildly on their sideline.

Where does psych come from?

The first records of the term psych come from the early 1900s. It is a shortening of the English psychoanalyze, meaning “to investigate the effects of the conscious and unconscious mind.”

Psych is also used as a slang term to mean “not” in a joking manner, as in I can’t stand you … psych! I love you. In this usage, psych usually follows a statement that is off-putting, upsetting, or unsettling, and the use of psych tells the listener that the speaker was only joking.

Psych is also used as a noun or adjective as a short form of psychology. Although it is informal, it’s often used by professionals and doctors of psychology, as well as the general public.

Did you know … ?

What are some other forms related to psych?

  • psyched (adjective)
  • psyche (variant spelling)

What are some synonyms for psych?

What are some words that share a root or word element with psych

What are some words that often get used in discussing psych?

How is psych used in real life?

Psych is most used to mean either to intimidate or to encourage. It’s also used in slang on its own as an exclamation (“Psych!”) to mean “not.”



Try using psych!

True or False?

Psych can mean to encourage someone and to scare someone.


What is psychology?

Psychology is the study of the mind, mental processes, and behaviors of humans and animals.

The term psychology is used to describe many specific areas of study. Generally, psychology is interested in the brain and, more specifically, why we think the way we do.

Because the mind is so complex, psychology is a very wide field with many subdivisions and branches of study. A few of the major areas of psychology include:

Both psychiatry and neuroscience are often confused with psychology. Like psychology, psychiatry also diagnoses and treats mental disorders but treatments are different. A psychiatrist is a medical doctor who can prescribe medicine for mental illnesses. A psychologist doesn’t often have a medical degree and instead treats patients with counseling and therapy, a process known as psychotherapy.

On the other hand, neuroscience is focused on the actual neurons, tissues, and synapses that physically make up the brain as an organ, rather than with how we think about things, as psychology is.

Even if they don’t know the specifics, most people are aware that psychology is a study of the mind and thinking. For this reason, the word psychology is often used to refer generally to a person’s thought process or mental state, as in In order to really know what happens during war, you need to understand a soldier’s psychology.

Why is psychology important?

The first records of the word psychology come from around 1675. It comes from the New Latin psȳchologia, which combines psycho, meaning “psyche” (which has to do with mental thinking), and logy, a combining form that indicates a science or field of study.

The concept of psychology can be traced back to ancient Greek philosophers such as Plato and Aristotle. As a scientific study, psychology is relatively new, started in the 1800s by Western scientists such as Wilhelm Wundt, William James, and Sigmund Freud. Freud in particular expanded psychological study to include the idea of subconscious thoughts that influence our behavior even if we are completely unaware of them.

Some branches of psychology can get pretty specific. Forensic psychology, for example, involves psychological analysis of people who interact with the law, such as witnesses or suspects, while sports psychology is concerned with athletes’ and sports teams’ training regimes.

Did you know … ?

One of the most infamous psychological experiments ever conducted was the 1971 Stanford Prison Experiment, run by psychologist Philip Zimbardo. The experiment had college students play the roles of prisoners and prison guards to analyze the psychological effects of prolonged imprisonment and power dynamics. The experiment was ended early due to the disturbing psychological effects it had on participants. This experiment has been heavily criticized on an ethical basis ever since.

What are real-life examples of psychology?

Psychology is a wide field of science that is constantly expanding.


Quiz yourself!

True or False?

Psychology is the study of mental disorders and the development of medication to treat them.

How to use psychology in a sentence

British Dictionary definitions for psychology

/ (saɪˈkɒlədʒɪ) /

noun plural -gies
the scientific study of all forms of human and animal behaviour, sometimes concerned with the methods through which behaviour can be modifiedSee also analytical psychology, clinical psychology, comparative psychology, educational psychology, experimental psychology
informal the mental make-up or structure of an individual that causes him or her to think or act in the way he or she does

Derived forms of psychology

psychologist, noun
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

Scientific definitions for psychology

[ sī-kŏlə-jē ]

The scientific study of mental processes and behavior.
The behavioral and cognitive characteristics of a specific individual, group, activity, or circumstance.Clinical psychology ♦ is the application of psychological knowledge to the diagnosis and treatment of patients.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Cultural definitions for psychology


The science dealing with mental phenomena and processes. Psychologists study emotions, perception, intelligence, consciousness, and the relationship between these phenomena and processes and the work of the glands and muscles. Psychologists are also interested in diseased or disordered mental states, and some psychologists provide therapy for individuals. In the United States, however, psychologists, unlike psychiatrists, are not medical doctors. (See psychiatry.)

notes for psychology

The two main divisions of psychology are individual or personality psychology and social psychology; social psychology deals with the mental processes of groups.
The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.