jointly

This term emphasizes a shared effort or a collective legal obligation. It is frequently used in professional, administrative, and legal registers to describe a partnership where responsibility is distributed equally or shared among multiple parties. It carries a neutral to formal tone and is often used to clarify that an action was not performed in isolation.

In legal contexts, it specifically denotes a state of shared liability or ownership, such as in the phrase "jointly and severally," which indicates that parties are responsible both as a group and as individuals. This distinguishes it from "separately" or "individually," where duties are partitioned rather than shared.