Regions of Nigeria
- Owa
- Owa
- Owa
- Owa
- Owa
- Owa
- Ovwori
- Ovwodokpokpor
- Ovwo
- Ovwakwa
- Ovuoku
- Ovungu
- Ovu Ngwu
- Ovukwa
- Ovu Inland
- Ovu
- Ovrode
- Ovoro
- Ovorji
- Ovworigbala Jeremi
- Ovor
- Ovonum
- Ovom
- Ovoaba
- Oviri-Olomu
- Oviri-Okpe
- Oviri-Ogor
- Oviri-Court
- Oviri
- Oviorie
- Ovim Station
- Ovim
- Ovim
- Ovia River
- Ovhororo
- Oforigbala
- Ovhori
- Overo
- Overe
- Ovan Camp
- Ovah
- Ovade
- Outer Reef
- Outar
- Ouree
- River Soda
- Otwa
- Otutuama
- River Otutu
- Oturkpo Nobi
- Oturkpicho
- Otuokpot
- Otuogori
- Otuocha
- Otunsoku
- Otunpa
- Otungbade
- Otun-Bale
- Otunbakoga
- Otunade
- Otun-Ekiti
- Otun
- Otun
- Otun
- Otun
- Otunba
- Otumara
- Otumara
- Otumakiri
- Otuma Forest Reserve
- River Otulu
- Otulu
- Otukwe
- Otukwang
- Otukpo
- Otukpa
- Otu-Jeremi
- Ofugo
- Otugbo
- Otugbembo
- Otor-Udu
- Otuba
- Otuasiga
- Otuapa
- Otuan
- Otuaka
- River Otu
- River Otu
- Otu
- Otu
- Otu
- Otu
- Otu
- Otu
- Otte
- Ota
- Otta
- Ototo-Lukoye
- Otoro Uruaotu
- Otoro-Nchara
- Otorofane
- Oton
- Otomo
- Otolu
- Otolokpo
- Otokutu
- Otokolopiri
- Otoka
- Otoja
- Otochi
- Otobi Station
- Otobi
- Otobaye Two
- Oto
- Otto
- Oti Oron
- River Otin
- Otibio
- Oteyi
- Oteyi
- Otete
- Otesin
- Otese
- Oteru
- Oteri
- Otere-Ofie
- River Otere
- Otere
- Otere
- Otere
- Oteleko
- Otegbo
- Otegbade
- Otefon Hill
- Otefon
- Otefe
- Ote-Etile
- Otor-Edo
- Oteda
- Ote
- Otatubu
- River Otata
- Otape
- Otan-Ile
- Otan Ayegbaju
- Otampa Station
- Otampa
- Otamnkaliki
- Otamiri River
- Otamakun
- Otafun
- Otaba
- River Ota-Alu
- Ota
- Osusu Aku
- Osusu
- Osogu
- Osuntedo
- Osunlepo
- Osunlade
- Osungboye
- Osun Ekiti
- Osun-Aro
- Osun
- Osun
- Osun
- Osuk Ita
- Oluke
- Osugh
- Osuakwa
- Osu
- Osu
- Osu
- Osu
- Osu
- Ezi-Ossu
- Osomari
- Ossissa-Stat
- Ossiomo Leper Settlement
- River Ossiomo
- River Osse
- Osowuelegan Iju
- Ososun
- Ososo Hill
- Ososo
- Ososa
- Oso Okwa
- Osonde
- Osonachu
- Osomegbe
- Osomari Forest Reserve
- Osolo-Kilarigbe
- Osokpuru
- Osokoro
- Osokoma
- Osoko
- Osok
- Osogun
- River Oso
- Oso