The Common Core State Standard and Next Generation Science Standards emphasize language and literacy across disciplines, requiring shifts in teaching practices and inventive approaches. This case study focuses on the instructional decision-making and activities of one uniquely experienced and qualified seventh-grade science teacher, whose English Language Arts background made her approach to vocabulary instruction distinctive, as she selected focus vocabulary and incorporated morphological instruction and lexical enhancement into science teaching practices. Results highlight the differences between content literacy and disciplinary literacy and the pitfalls of applying broad literacy strategies without deep consideration of disciplinary knowledge and requirements and provide examples of naturalistic ways to incorporate morphology instruction into science instructional conversations to enhance students’ relational knowledge.