Thaddius is a distinctive boys' name in United States, ranking #11976 in 2021 with 6 recorded births. This places Thaddius in the bottom 15% of ranked US boys' names for the year. Its actual usage is classified as Rare. The name reached its all-time peak in 2001 with 12 births ranking #5975. In 2021, approximately 1 in every 291,373 boys born was named Thaddius. FALLING Recent data shows the name is currently falling.