Abbreviation for luteinizing hormone.
1 left hand
2 luteinizing hormone

In musical notation, abbreviation for “left hand”, directing a pianist to use the left hand. This is usually in order to facilitate a technically difficult passage, dividing the notes between both hands rather than playing the passage solely with the right hand. It can also be notated in French as M.G. (main gauche) or in Italian as M.S. (mano sinistra). The opposite is R.H. (“right hand”).