- Carl Jung
- Carl Rogers
- Carl Wernicke
- Case Study Methodologies
- Catharsis
- Cathexis
- Central Nervous System
- Character
- Charles Edward Spearman
- Charles Robert Darwin
- Child Abuse
- Child Development
- Child Psychology
- Childhood
- Christiana Drummond Morgan
- Christine Ladd-Franklin
- Clark Leonard Hull
- Classical Conditioning
- Client-Centered Therapy
- Clifford Beers
- Clinical Psychology
- Cliques
- Codependence
- Cognition
- Cognitive Behavior Therapy
- Cognitive Development
- Cognitive Dissonance
- Cognitive Psychology
- Cognitive Therapy
- Color Vision
