This study examined lay individuals’ use of narrative and figurative language for communicating biomedical and psychosocial concepts in online alcoholism discussion forums. We performed quantitative and qualitative analyses of content, narrative, and figurative language on 311 opening forum posts. Linguistic patterns indicated a distinction between narrative and figurative functions of language in communication that is sensitive to the concreteness of the content. Individuals were more likely to use narrative to convey concrete psychosocial content, and figurative language to convey abstract psychosocial content. Individuals did not use narrative or figurative language to communicate abstract, technical biomedical content. Although they belong to the biomedical model, concrete physical symptoms receive treatment in a manner more similar to concrete psychosocial content than more abstract, technical biomedical content. Our findings suggest that individuals’ use of narrative and figurative language is largely driven by the concreteness or perceptibility of the underlying content rather than the content domain.