cosignitary
/kɒˌsaɪɡˈnætəri/ or /kəˌsaɪɡˈneɪtəri/Definitions
1. noun
A person or entity who signs a document jointly with the main signatory or is jointly and severally liable with another party for the payment of a debt or performance of a contract.
“The cosignatory on the loan agreement is equally responsible for repaying the debt.”
2. adjective
Jointly signing or jointly liable.
“The cosignatory clause in the contract has caused a controversy among the parties involved.”