Rather with divided effort can be replaced with several synonyms depending on the context. For instance, "partially" can be used to indicate that an action was carried out only to a certain extent. "Partly" can be used in a similar manner and often conveys a sense of incomplete accomplishment. "Singly" is another synonym that denotes an action carried out by one person or entity alone. Alternatively, "individually" may be used to describe efforts made by a group of individuals who are not working together. "Distractedly" is yet another synonym used to describe the lack of focus and attention in a task, which results in the division of effort.