masc. proper name, from Latin Thaddaeus, from Greek Thaddaios, from Talmudic Hebrew Tadday. Klein derives this from Aramaic tedhayya (pl.) "breasts." Thayer's "Greek-English Lexicon of the New Testament" suggests the sense might be "large-hearted," hence "courageous." In the Bible, a surname of the apostle Jude, brother of James the Less.