further

(Old English: (first meaning), more forward; (current meaning), in addition, to a grater degree)

further
furtherance
furtherer
furtherest
furthermore (adverb) (not comparable)
An indication that there is more information to be presented: Furthermore is a useful word when anyone has another point to make in an argument or an explanation.

The word furthermore is often used at the beginning of a sentence and it is usually followed by a comma; as, "Mac skillfully took charge of the going away party for his friend, furthermore, he even stayed afterwards to clean up everything.''

furthermost (adjective)