Rainer is a masculine given name of Germanic origin, derived from the Old German word "Raginarius", which means "spear power". It was initially used as a surname and later adopted as a first name. The name Rainer is associated with several notable individuals throughout history, including the German composer Rainer Maria Rilke and the Austrian film director Rainer Werner Fassbinder.
"Rainer experienced a notable dip in popularity between 2010 and 2020, with only half the number of babies given the name in 2020 compared to the preceding decade."