means A word covering several distinct things — a persuasive sales talk, a sticky black tar from distilling resin or coal, the highness or lowness of a sound, the act of throwing, and the steepness of a slope or roof.

from Two unrelated roots collided into one spelling. The black-tar 'pitch' descends from Old English 'pic', borrowed from Latin 'pix' (the sticky stuff), a cousin of words across Europe for resin and tar. The throwing/leaning 'pitch' is a separate Middle English verb 'picchen', meaning to thrust, fix, or set in place — from which we get pitching a tent, a ship pitching on waves, the pitch of a roof, and the modern sense of pitching a deal. The musical sense of 'pitch' grew out of that same throwing-and-setting idea, the level at which a note is 'set'.