Meaning A boy's name of Greek origin, it means "Thaddeus was one of the 12 apostles described in the New Testament of the Bible." Origin of Thaddius Greek +-100%Zoom level changed to 1 Popular Middle Names Garrod Pronunciation 🔊 Listen Thaddius Similar Names Thad Thadeus Phil Pip Thomas Tim Baithazar Darrian Darrien Thomas George Year by Year Popularity of Thaddius