Thaddius is a distinctive boys' name in United States, ranking #6043 in 2002 with 12 recorded births. The name reached its all-time peak in 2001 with 12 births ranking #5975. Since 1996, the popularity has increased by 100.0%. In 2002, approximately 1 in every 161,789 boys born was named Thaddius. FALLING Recent data shows the name is currently falling.