psychology

noun

psy·​chol·​o·​gy sī-ˈkä-lə-jē 

plural psychologies

1

: the science of mind and behavior

studied psychology in college

2

a

: the mental or behavioral characteristics of an individual or group

the psychology of athletes

We need to understand the psychologies of the two people involved in the incident.

Which fear is more likely to rule the day has to do with each person's psychology and perception of risk.

—Hannah Herrera Greenspan

b

: the study of mind and behavior in relation to a particular field of knowledge or activity

the psychology of learning

3

: a theory or system of psychology

Freudian psychology

the psychology of Jung

Did you know?

The Roots of Psychology

The word psychology was formed by combining the Greek psychē (meaning “breath, principle of life, life, soul,”) with –logia (which comes from the Greek logos, meaning “speech, word, reason”). An early use appears in Nicholas Culpeper’s mid-17th century translation of Simeon Partliz’s A New Method of Physick, in which it is stated that “Psychologie is the knowledg of the Soul.” Today, psychology is concerned with the science or study of the mind and behavior. Many branches of psychology are differentiated by the specific field to which they belong, such as animal psychology, child psychology, and sports psychology.

Examples of psychology in a Sentence

She studied psychology in college.

the psychology of an athlete

the psychology of crowd behavior

We need to understand the psychologies of the two people involved in the incident.

Recent Examples on the Web

How Clarke reached this rarefied realm of cinematic creation—and then largely left it behind—is an exemplary story of artistic psychology, film history, and social politics. — Richard Brody, New Yorker, 26 Aug. 2026

Conspiracy theories have gone viral, prompting rebuttals of claims from reporters covering the case and experts in crime scene investigation and forensic psychology. — Sumiko Corley, NBC news, 26 Aug. 2026

Instead, a thoughtful blend of science, psychology, and ongoing support is essential for those pursuing long-term health and wellness. — Nia Bowers, USA Today, 25 Aug. 2026

After being convicted for shooting a rival gang member, Daniels, now 31, is a PhD student in psychology and social intervention at New York University. — Rocco Parascandola, New York Daily News, 23 Aug. 2026

Word History

Etymology

New Latin psychologia, from psych- + -logia -logy

First Known Use

1749, in the meaning defined at sense 1

Phrases Containing psychology

• abnormal psychology
• analytical psychology
• analytic psychology
• clinical psychology
• depth psychology
• educational psychology
• evolutionary psychology
• Gestalt psychology
• industrial psychology
• physiological psychology
• reverse psychology
• social psychology

Rhymes for psychology

• anthology
• apology
• astrology
• biology
• christology
• chronology
• conchology
• cosmology
• cryptology
• cytology
• doxology
• ecology

Kids Definition

psychology

noun

psy·​chol·​o·​gy sī-ˈkäl-ə-jē 

plural psychologies

1

: the science or study of mind and behavior

2

: the particular ways in which an individual or group thinks or behaves

Etymology

from scientific Latin psychologia "the study of the mind and behavior," derived from Greek psychē "soul, mind" and Greek -logia "science, study"

Medical Definition

psychology

noun

psy·​chol·​o·​gy -jē 

plural psychologies

1

: the science of mind and behavior

2

a

: the mental or behavioral characteristics typical of an individual or group or a particular form of behavior

mob psychology

the psychology of arson

b

: the study of mind and behavior in relation to a particular field of knowledge or activity

color psychology

the psychology of learning

3

: a treatise on or a school, system, or branch of psychology