Can be confused: beside, besides (see usage note at beside).
Synonyms 1. further. Besides, moreover both indicate something additional to what has already been stated. Besides often suggests that the addition is in the nature of an afterthought: The bill cannot be paid as yet; besides, the work is not completed.Moreover is more formal and implies that the addition is something particular, emphatic, or important: I did not like the house; moreover, it was too high-priced.