Θαδδαῖος Save Could not find Θαδδαῖον in Logeion dictionaries. Θαδδαῖον Proper-name noun masculine accusative singular of Θαδδαῖος See Θαδδαῖον in Morpho Abbott-Smith NT Number of occurrences in NT: 2Strong 2280 Θαδδαῖος, -ου, ὁ (Aram. תַּדִאַי, תַּדַּי), Thaddæus: Mt 10:3, Mk 3:18 (WH, mg., Λεββαῖος, q.v.).†