Rainier is a distinctive boys' name in United States, ranking #6189 in 2007 with 14 recorded births. The name reached its all-time peak in 2023 with 41 births ranking #3045. Since 1996, the popularity has increased by 55.6%. In 2007, approximately 1 in every 148,231 boys born was named Rainier. FALLING Recent data shows the name is currently falling.