Webster’s Revised Unabridged Dictionary · 1913
Sphragistics
Sphra·gis′tics (sfrȧ·jĭs′tĭks), n. [Gr. σφραγιστικός of or for sealing, fr. σφραγίς a seal.] The science of seals, their history, age, distinctions, etc., esp. as verifying the age and genuiness of documents.