Thomasin is a distinctive girls' name in United States, ranking #14934 in 2020 with 6 recorded births. This places Thomasin in the bottom 15% of ranked US girls' names for the year. Its actual usage is classified as Rare. The name reached its all-time peak in 2023 with 16 births ranking #7212. In 2020, approximately 1 in every 269,252 girls born was named Thomasin. FALLING Recent data shows the name is currently falling.