O - Oaks
Oan - Obafunwa
Obafunwa - Oberling
Oberlton - Obioha
Obioha - Obrien
Obrien - Ockimey
Ockleberry - Odame
Odams - Oderinde
Oderinde - Odom
Odom - Odoms
Odoms - Odumosu
Odums - Offiah
Offiah - Ofori
Ofori - Ogbonna
Ogbonna - Ogle
Ogle - Ognibene
Ognibene - Ogundele
Ogundele - Ogunnaya
Ogunnaya - Ogunyemi
Ogunyemi - Ojedapo
Ojedele - Ojumu
Ojuri - Oke
Oke - Okeke
Okeke - Okezie
Okezie - Okolo
Okolo - Okoronkwo
Okoronkwo - Okubanjo
Okubanjo - Ola
Ola - Oladiran
Oladiran - Olaode
Olaofe - Olde
Olde - Oligbo
Olimene - Oliver
Oliver - Oliver
Oliver - Oliver

Oliver - Ollie
Ollie - Olowo
Olowo - Olukolu
Olukolu - Ombaka
Ombongi - Omotosho
Omotosho - Oneal
Oneal - Oneal
Oneal - Oni
Oni - Onuoha
Onuoha - Onyeji
Onyeji - Opara
Opara - Orakwue
Oramulu - Oreta
Orey - Orok
Orok - Orr
Orr - Orusakwe
Orvek - Osborne
Osborne - Osbourne
Osbourne - Osei
Osei - Osinowo
Osinowo - Osueke
Osueke - Otis
Otis - Oubre
Oubre - Ousmane
Ousmane - Outley
Outley - Overman
Overman - Oviatt
Oviatt - Owens
Owens - Owens
Owens - Owens
Owens - Owens
Owens - Owu
Owuama - Oxford
Oxford - Oyetuga
Oyetunbi - Ozvath