Of uncertain origin; Thaddaeus, one of the Apostles -- Thaddaeus.
Thayer's Greek Lexicon
Strong's 2280: Θαδδαῖος
Θαδδαῖος, Θαδδαιου, ὁ (תַּדַּי, perhaps large-hearted or courageous, although it has not been shown that תַּד equivalent to the Hebrew שַׁד can meanpectus as well asmamma; (some would connect the terms by the fact that the 'child of one's heart' may be also described as a 'bosom-child'; but see B. D. under the word )), Thaddeus, a surname of the apostle Jude; he was also called Lebbaeus and was the brother of James the less: Matthew 10:3 R G L Tr WH; Mark 3:18. (Cf. B. D. under the word; Keil on Matthew, the passage cited; WH's Appendix, p. 11b. The latter hold the name Λεββαῖος to be due to an early attempt to bring Levi (Λευεις) the publican (Luke 5:27) within the Twelve.)
Matthew 10:3 - N-NMS GRK:Ἁλφαίου καὶ Θαδδαῖος NAS: the son of Alphaeus, and Thaddaeus; KJV: Lebbaeus, whose surname was Thaddaeus; INT: of Alphaeus and Thaddaeus
Mark 3:18 - N-AMS GRK:Ἁλφαίου καὶ Θαδδαῖον καὶ Σίμωνα NAS: the son of Alphaeus, and Thaddaeus, and Simon KJV: of Alphaeus, and Thaddaeus, and Simon INT: of Alphaeus and Thaddaeus and Simon
