Exploring Definitions of “Addiction” in Adolescents and Young Adults and Correlation with Substance Use Behaviors

(1) Background: Young people engage in addictive behaviors, but little is known about how they understand addiction. The present study examined how young people describe addiction in their own words and correlations between their definitions and substance use behaviors. (2) Methods: Young adults (n = 1146) in the PACE Vermont Study responded to an open-ended item “what does “addiction” mean?” in 2019. Responses were coded using three inductive categories and fifteen subcategories. Quantitative analyses examined correlations between addiction theme definitions, demographics, and substance use behaviors. (3) Participants frequently defined addiction by physiological (68%) and psychological changes (65%) and less by behavioral changes (6%), or all three (3%); young adults had higher odds of defining addiction as physiological or behavioral changes than adolescents. Participants who described addiction as “psychological changes” had lower odds of ever electronic vapor product use (OR 0.75, 95% CI 0.57–1.00) than those using another definition, controlling for age and sex. (4) Perceptions of addiction in our sample aligned with existing validated measures of addiction. Findings discriminated between familiar features of addiction and features that may be overlooked by young adults. Substance users may employ definitions that exclude the symptoms they are most likely to experience.