Rainier is a distinctive boys' name in United States, ranking #11205 in 1999 with 5 recorded births. The name reached its all-time peak in 2023 with 41 births ranking #3045. Since 1996, the popularity has decreased by 44.4%. In 1999, approximately 1 in every 384,017 boys born was named Rainier. FALLING Recent data shows the name is currently falling.