These names are from a list of 6000 names given to Finnish children (aged 1 to 10 years old). Some of the names may seem ordinary to Anglophones, but in Finland they're still considered rare and/or unique.
OdeliaOdessaOdetteOdina
Oleanna
OleksandraOlenaOlesia
Olga-Ester
Olga-Liisa
Olga-Maija
Oline
OliwiaOma - means "own" in Finnish
Omelia
Omena - means "apple" in Finnish
OnaOnerva
Oninda
Onna
Onneli
Oodi - means "ode" in Finnish
Oona-Alisa
Oona-Amanda
Oona-Elene
Oona-Sofia
Oosa
Opri
OrvokkiOsmi
Otilia / Ottiilia