Developmental language disorder is an academic concept and research field concerned with the investigation of persistent difficulties in acquiring and using language across modalities (spoken, written, sign language) due to deficits in comprehension or production, not attributable to hearing impairment, intellectual disability, neurological conditions, or other medical conditions. This field examines the underlying cognitive, biological, and environmental factors contributing to these difficulties, their impact on developmental trajectories and academic outcomes, and the development and evaluation of assessment and intervention strategies, highlighting its significance for understanding typical and atypical language development and informing clinical practice.