cosignatory
/koʊˈsɪɡnəˌtɔri/
noun
- A person or party that signs a document (such as a treaty, contract, or agreement) together with others.
- The contract requires the approval of every cosignatory before it becomes valid.
- Each cosignatory to the peace treaty pledged to uphold the terms.
- She was a cosignatory to the international climate agreement.
adjective
- Relating to or being one of the parties that signs a document jointly.
- All cosignatory members must attend the annual review meeting.
- The cosignatory companies shared responsibility for the project's success.
- The cosignatory nations agreed to reduce carbon emissions by 2030.