Thaddaeus is a distinctive boys' name in United States, ranking #4963 in 2011 with 19 recorded births. The name reached its all-time peak in 2005 with 29 births ranking #3444. Since 1996, the popularity has decreased by 20.8%. In 2011, approximately 1 in every 99,947 boys born was named Thaddaeus. FALLING Recent data shows the name is currently falling.