After studying the difference between もう and まだ (which seems clear to me now), I realize that there seems to be two different words spelled もう, which apparently have different pitch accents; high to low for the もう meaning "already", low to high for the (additive?) もう meaning "another".
Are they actually different words and are those definitions correct? I don't seem to find much information concerning the pitch accents as well as the proper definitions in Japanese dictionaries (because my level is too low and Google Translate isn't accurate).