English Reference
noun · adjective

signatory

n. · adj.
US /ˈsɪɡnəˌtɔɹi/ UK /sˈɪɡnətəɹˌi/ sig·na·to·ry UK spelling signatories

  1. 01 C1 Advanced Formal Law

    n.a person, company, or country that has signed an official document or agreement.

    n.a person or entity that is a party to a formal agreement, treaty, or contract by virtue of having signed it.

    Simple

    Both countries were signatories to the peace treaty signed last year.

    In context

    As a primary signatory to the international climate accord, the nation committed to reducing its carbon emissions by forty percent over the next decade.

    Usage

    Usually followed by the preposition 'to'.

    Teacher's tip

    This word is almost exclusively used in legal, political, or highly formal business contexts; for everyday situations, 'the person who signed' is preferred.

  2. 02 C1 Advanced Formal Law

    adj.describing a person or group that has signed an agreement.

    adj.having signed or joined in a signature; often used to describe the status of a nation or body in relation to a treaty.

    Simple

    The signatory powers met in Geneva to discuss the new trade rules.

    In context

    The signatory nations were required to ratify the agreement within their own domestic legislatures before the end of the fiscal year.

    Usage

    Typically used before a noun like 'nations', 'powers', or 'parties'.

    Teacher's tip

    In modern English, the noun form is much more common than the adjective form.

    non signatory

More than £90,000 has now been raised for Arday's family, after Windrush campaigner Sir Patrick Vernon, who is also among the signatories to the petition, launched a fundraiser.

BBC News· 16 Aug 2026

Türkiye became a signatory in 1990 and ratified the convention in 1994.

UN News· 13 Aug 2026

From Latin signatorius.

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

This entry
Origin Latin signatorius
Level C1 · Advanced
Frequency Occasional
Updated