Seith is a distinctive boys' name in United States, ranking #10129 in 2000 with 6 recorded births. This places Seith in the bottom 16% of ranked US boys' names for the year. Its actual usage is classified as Rare. The name reached its all-time peak in 1999 with 12 births ranking #5595. In 2000, approximately 1 in every 327,322 boys born was named Seith. FALLING Recent data shows the name is currently falling.