Designation used in piano music indicating that a specific passage is to be played by the left hand. C.s. are the initials for the Italian words colla sinistra ( colla means with and sinistra means left implying the left hand). Colla can also be shortened to col, so col sinistra would mean the same as colla sinistra.See also [Eng.] L.H. ; [Eng.] left hand; [Fr.] M.g. ; [Fr.] main gauche; [It.] M.s. ; [It.] mano sinistra; [It.] colla sinistra; [It.] col sinistra.Also [Eng.] R.H. ; [Eng.] right hand; [Fr.] M.d. ; [Fr.] main droite; [It.] M.d. ; [It.] mano destra; [It.] C.d. ; [It.] colla destra; [It.] col destra.