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

Changes in the adolescent brain make teenagers increasingly attentive to their social worlds, says Wayne State University psychology professor Hannah Schacter. — Ashley Lynch, Sacbee.com, 12 Oct. 2026

Dark Land explores cold cases in in Wales related to more than 100 unsolved murders, and brings in investigators from policing and psychology to revisit them. — Jesse Whittock, Deadline, 12 Oct. 2026

Nonetheless, Sam Huszczo, chief investment officer at SGH Wealth Management, thinks the market's bull run — which has seen multiple record highs this year alone — is feeding a shift in investor psychology, and margin debt is one sign. — Sean Conlon, CNBC, 9 Oct. 2026

Ramirez went to Bronx Leadership Academy before studying psychology at Baruch College, according to her LinkedIn page. — Theodore Parisienne, New York Daily News, 8 Oct. 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