The term "de-signatory" is often used to refer to someone who has ceased to be a signatory of a particular agreement or treaty. Some synonyms that can be used in place of "de-signatory" include "former signatory," "withdrawn signer," "ex-participant," or "former party." Other possible synonyms could include terms such as "former member," "lapsed member," or even "former adherent." Regardless of the exact choice of synonym, the underlying meaning remains the same: this is a person who was once a signatory or member of a particular group, but who is no longer bound by the terms of that agreement or commitment.