- Name - OBADIAH
Meaning - SERVANT OF GOD
- Name - OBAID
Meaning - SMALL SLAVE
- Name - OBERON
Meaning - ELF RULER
- Name - OBERT
Meaning - WEALTHY AND BRIGHT
- Name - OBI
Meaning - HEART
- Name - OBINNA
Meaning - FATHER'S HEART
- Name - OCTAVIAN
Meaning - BORN EIGHTH
- Name - OCTAVIO
Meaning - EIGHTH CHILD
- Name - OCTAVIUS
Meaning - EIGHTH BORN
- Name - ODEN
Meaning - INSPIRATION
- Name - ODI
Meaning - WEALTHY DEFENDER
- Name - ODIN
Meaning - INSPIRATION
- Name - ODOM
Meaning - SON IN LAW
- Name - ODRAN
Meaning - PALE
- Name - ODYSSEUS
Meaning - WRATHFUL
- Name - OEMAR
Meaning - THE ARABIAN TRAVELER
- Name - OFER
Meaning - YOUNG DEER
- Name - OGUZ
Meaning - ARROW
- Name - OHAD
Meaning - PRAISING
- Name - OLA
Meaning - WEALTH
- Name - OLADELE
Meaning - HONORS
- Name - OLAF
Meaning - ANCESTOR'S HEIRLOOM
- Name - OLAV
Meaning - ANCESTOR'S RELIC
- Name - OLAVI
Meaning - FAMILY DESCENDANT
- Name - OLEG
Meaning - HOLY
- Name - OLGIERD
Meaning - FAME
- Name - OLIN
Meaning - HOLLY
- Name - OLIVA
Meaning - MEANING UNKNOWN
- Name - OLIVER
Meaning - OLIVE TREE
- Name - OLIVIER
Meaning - FROM THE OLIVE TREE
- Name - OLIVIERO
Meaning - AN OLIVE TREE
- Name - OLIVIO
Meaning - OLIVE TREE
- Name - OLLE
Meaning - FAMILY DESCENDANT
- Name - OLLIE
Meaning - OLIVE TREE
- Name - OLLIVER
Meaning - PEACEFUL
- Name - OMARR
Meaning - HIGHEST
- Name - OMERO
Meaning - SECURITY
- Name - OMMAR
Meaning - FIRST SON
- Name - OMRI
Meaning - SHEAF OF CORN
- Name - ON
Meaning - PAIN
- Name - ONDREI
Meaning - MAN WARRIOR
- Name - ONDREJ
Meaning - MANLY
- Name - ONNI
Meaning - HAPPINESS
- Name - ONOFRIO
Meaning - PEACE
- Name - ONUR
Meaning - HONOR
- Name - OPHIR
Meaning - FRUITFUL REGION
- Name - ORAZIO
Meaning - TIMEKEEPER
- Name - ORD
Meaning - SPEAR
- Name - ORDELL
Meaning - BEGINNING
- Name - ORESTE
Meaning - MAN OF THE MOUNTAIN
- Name - ORESTES
Meaning - MAN OF THE MOUNTAIN
- Name - ORHAN
Meaning - ARMY COMMANDER
- Name - ORIN
Meaning - WHITE
- Name - ORLAND
Meaning - RENOWNED IN THE LAND
- Name - ORLANDO
Meaning - RENOWNED IN THE LAND
- Name - ORLONDO
Meaning - RENOWNED IN THE LAND
- Name - ORM
Meaning - SON OF ULF
- Name - ORMAND
Meaning - RED
- Name - ORPHEUS
Meaning - BEAUTIFUL VOICE
- Name - ORSON
Meaning - BEAR LIKE
- Name - ORTON
Meaning - FROM THE SHORE FARM
- Name - ORUN
Meaning - LIGHT
- Name - ORVIL
Meaning - GOLDEN VILLAGE
- Name - ORVILLE
Meaning - GOLDEN VILLAGE
- Name - OSAMA
Meaning - LION
- Name - OSBERT
Meaning - DIVINELY BRILLIANT
- Name - OSBORNE
Meaning - DIVINE BEAR
- Name - OSBOURNE
Meaning - DIVINE WARRIOR
- Name - OSCAR
Meaning - GOD'S SPEAR
- Name - OSGAR
Meaning - GOD SPEAR
- Name - OSKA
Meaning - DIVINE SPEAR
- Name - OSKAR
Meaning - DIVINE SPEAR
- Name - OSMAR
Meaning - DIVINELY GLORIOUS
- Name - OSMOND
Meaning - DIVINE PROTECTION
- Name - OSRIC
Meaning - DIVINE RULER
- Name - OSRICK
Meaning - DIVINE RULER
- Name - OSSIAN
Meaning - YOUNG DEER
- Name - OSSIE
Meaning - DIVINE SPEAR
- Name - OSSY
Meaning - DIVINE SPEAR
- Name - OSVALDO
Meaning - GOD'S POWER
- Name - OSWALD
Meaning - DIVINELY POWERFUL
- Name - OSWELL
Meaning - DIVINELY POWERFUL
- Name - OSWIN
Meaning - DIVINE FRIEND
- Name - OTHELLO
Meaning - PROSPEROUS
- Name - OTHMAN
Meaning - WEALTHY
- Name - OTIS
Meaning - SON OF OTTO
- Name - OTMAR
Meaning - GREAT
- Name - OTTAVIO
Meaning - BORN EIGHTH
- Name - OTTIS
Meaning - SON OF OTTO
- Name - OTTO
Meaning - FORTUNE
- Name - OTWAY
Meaning - LUCKY IN WAR
- Name - OUSAMA
Meaning - MEANING UNKNOWN
- Name - OVID
Meaning - WORKER
- Name - OVIDIU
Meaning - WORKER
- Name - OVIN
Meaning - HANDSOME
- Name - OWEN
Meaning - HELP FROM ALLAH
- Name - OWEYN
Meaning - MEANING UNKNOWN
- Name - OZAN
Meaning - POET
- Name - OZMEN
Meaning - MEANING UNKNOWN
- Name - OZZIE
Meaning - DIVINE POWER