The word "再说" is formed by combining the character "再", which means "again" or "further", with "说", meaning "to speak" or "to say". This results in a literal sense of "speak again", but in usage, it functions as a conjunction or phrase meaning "besides" or "moreover" to introduce an additional point, or it can indicate postponement, as in "discuss later". The formation is simply the modification of "说" by "再" to convey repetition or continuation in speech.