Osa is a rare name, likely the Anglicized spelling of Aase, a variant of Åse, an Old Norse feminine name (and name element) meaning "god." Surprisingly, it also means "godlike" in African Bini. There is an Osa in The Dictionary of African Mythology.
Unfortunately, Osa in all capital letters - OSA, stands for 'obstructive sleep apnea.' Osa is also Russian and Polish for "wasp" and the Spanish equivalent of ursa, "bear." I don't find any of these too negative to remove Osa from being seriously considered as a name today, and in fact I find the nature meanings a plus.
Osa Johnson and husband Martin were explorers focused on the wild habitats of exotic countries who made documentary films.
Danish actress Osa Massen, a stunning beauty, was born in 1914. She was born Aase Iverson Madsen and started her career as a newspaper photographer.
Osa was not unheard of between 1880 and 1920. The most it was given, however, was to 21 girls in 1892 and 21 girls in 1918. After 1930 it was used on and off until 1964, until dropping out of the name race for a few decades only to reappear once in 2011, when it was used on 6 girls.