Entry 2 senses · 2 variants Webster, 1913 Deletery · Del·e·ter·y · IPA /dəˈliːtəɹi/ a. n. 01 a. Destructive; poisonous. 1. Destructive; poisonous.[Obs.] 02 n. That which destroys. 1. That which destroys.[Obs.] “They [the Scriptures] are the only deletery of heresies.” — Jer. Taylor.