In design, a wireframe refers to a low-fidelity visual representation of a website or application layout. It serves as a blueprint that outlines the structure, content placement, and functionality without focusing on visual design elements like color or typography. Wireframes help designers and stakeholders visualize the interface and user journey, allowing for early feedback and adjustments before development begins. They are essential for communicating ideas and requirements among team members, facilitating efficient project progression while ensuring that user experience considerations are maintained throughout the design process.