<p><strong>Noun</strong></p><ul><li>an enclosing framework on casters or wheels for supporting a baby who is learning to walk</li><li>a similar mobility aid, usually a waist-high four-legged framework of lightweight metal, for support or balance while walking</li><li>a person or thing that walks or likes to walk: He's a great walker</li><li>an extra or supernumerary</li><li>a musician required by a union contract to be hired and paid full salary even when not needed for performance</li></ul>