There are several synonyms for the phrase "hold one's end" which convey the idea of fulfilling one's responsibilities or obligations. One synonym is "pull one's weight," which suggests that everyone on a team or in a group should contribute equally to achieve success. Another synonym is "do one's part," which likewise implies that each individual has a role to play in reaching a common goal. "Carry one's weight" is another synonym which emphasizes the importance of personal responsibility and accountability. Overall, these synonyms remind us of the significance of teamwork and individual effort in achieving success, and of the need for each person to contribute their fair share.