"Lil Rousin'" is an original composition by tenor saxophonist Charlie Rouse, recorded for his 1960 album Yeah! on the Epic label. Rouse is best known for his long tenure as Thelonious Monk's saxophonist from 1959 to 1970, but the Yeah! sessions captured him stepping out as a leader in his own right, fronting a quintet that showcased his personal compositional voice. The tune reflects Rouse's characteristically warm, deliberate approach to hard bop, featuring the kind of angular melodic writing that made him such a natural fit for Monk's music while standing on its own terms. Rouse had a gift for composing lines that sounded deceptively simple but contained rhythmic and harmonic twists that rewarded close listening. On this track, Billy Gardner's piano comping provides a buoyant foundation, and the interplay between the two musicians demonstrates the easy rapport the group developed during these sessions. "Lil Rousin'" is a fine example of Rouse's underappreciated work as a bandleader and writer, offering a window into the creative mind of a musician whose identity was often overshadowed by his famous employer. The composition stands as evidence that Rouse was far more than a skilled sideman, possessing a distinctive compositional sensibility rooted in the hard bop tradition.