150 Boy Names That Start With O: for Outstanding Boys

Only boy names that start with O are original and out-of-this-world.

What does the letter O bring to the party? It brings optimism, opportunity, and outstanding names. Boy names that start with O are outrageous, original, and sometimes opulent. And they come from every corner of the globe, embracing different cultures, languages, and beliefs.

So, sit back and enjoy the ride as we list 150 male names that start with O to kickstart your naming inspiration.

150 Out-of-This-World Boy Names With O

Open your eyes to a world filled with O names for boys.

  1. Oak – derived from the Anglo-Saxon word “ac,” meaning “oak,” representing “dwellers near a prominent oak tree.”
  2. Oakleigh – derived from the Old English name Accleia, meaning “from the oak meadow.”
  3. Oakley – an alternate spelling of Oakleigh with the same meaning and origin.
  4. Oaklynn – this gender-neutral Welsh name means “oak pond.”
  5. Oates – of Middle German, Old English, and Norman origin, meaning “prosperity and wealth.”
  6. Oba – the first Nigerian name to make the list is regal – Oba means “king.”
  7. Obadias – a classic Hebrew boy’s name meaning “servant of God.”
  8. Obadya – a variant of Obadiah with the same meaning and origin.
  9. Obafemi – some O names for boys are African – Obefami means “king” in Nigerian.
  10. Obama – this famous East African/Kenyan name means “to bend or lean.”
  11. Obediah – a variant of the Hebrew name Obadiah, meaning “servant of God.”
  12. Oberon – a cool Shakespearean character – Oberon means “noble and bear-like” in German.
  13. Obert – a rare French-inspired name meaning “noble and bright.”
  14. Obi – a unique Nigerian name meaning “heart.”
  15. Obie – a short form of Obadiah, this Hebrew name means “servant of God.”
  16. O’Brien – from the Irish and Gaelic language, meaning “descendant of Brian.”
  17. Oceanus – a rare Greek male name meaning “of the ocean.”
  18. Ochs – is an unusual High German nickname for a stubborn person, meaning “ox.”
  19. Octaveous – this Roman clan name means “born eighth.”
  20. Octavien – the perfect Latin name for someone whose favorite number is eight – means “eighth.”
  21. Octavo – a variation of the Latin Octavien, meaning “in eighth” or “for the eighth time.”
  22. Odall – possibly a variation of the Old English Odell, meaning “woad hill,” a plant used in dye.
  23. Odd – some boy names with O are unusual – Odd means “arrow or blade edge” in Scandinavian.
  24. Odean – in Jamaica, it means “advisor, and “descendant of the deacon” in Irish.
  25. Odell – derived from the Old English “woad hill,” a plant used for making dye.
  26. Odeon – the perfect name for musical baby boys – Odeon means “singing place” in Greek.
  27. Odera – of South Eastern Nigerian origin, meaning “once God writes it.”
  28. Odhran – some boy names that start with O are Irish – Odhran means “little pale-green one.”
  29. Odie – a shortened nickname derived from Odell, meaning “woad hill” (a flower used for dye).
  30. Odilo German names like this are so descriptive – meaning “fortunate or prosperous in battle.”
  31. Odin – the father of all Norse gods – Odin means “lord of frenzy.”
  32. Odis – derived from the Old High German “ot,” meaning “prosperous and wealthy.”
  33. Odolf – this German name derives from Adolf and means “noble or majestic wolf.”
  34. Odon – of Old English and Hungarian origin, meaning “wealthy defender or protector.”
  35. Odysse – a famous name from Greek mythology, meaning “story of Odysseus.”
  36. Odysseus – derived from the Greek verb “odussomai,” meaning “to be angry” or “hate.”
  37. Ofeer – inspired by the biblical place Ophir, meaning “gold” in Hebrew.
  38. Ogbanna – this Southern Nigerian name derives from Ogbonna and means “he resembles his father.”
  39. Ogdan – some guy names that start with O are English – Ogdan means “from the oak valley.”
  40. Ogden – an alternate spelling of the Old English Ogdan, meaning “from the oak valley.”
  41. Ogun – some Nigerian names have great meanings, like Ogun, meaning “god of war and metals.”
  42. Ohad – if your child is “cherished” and worthy of “praise,” this Hebrew name nails it.
  43. Ohed – of Hebrew origin, meaning “loved one” and “servant of God.”
  44. Ohene – taken from the Ghanian Akan tribe, meaning “king.”
  45. Ohndre – this foreign name is of Greek and French origin and means “man or warrior.”
  46. Ohnjel – this 6-letter unisex Greek name means “messenger of God.”
  47. Ohtli – a gender-neutral Aztec name meaning “road or path.”
  48. Oisin – this rare 5-letter Irish name means “little deer” or “fawn.”
  49. Okafo – a Nigerian Igbo name meaning “born on Afor (market) day.”
  50. O’Keefe – this Irish boy’s name means “descendant of Keefe” and “kind and noble.”
  51. Okeli – an unusual Nigerian name describing someone “born on Orie,” one of four market days.
  52. Okonkwo – another Nigerian “market day” name, meaning “man born on Nkwo day.”
  53. Okotto – our first Japanese entry on the list means “boar tribe.”
  54. Olaff – a cool Scandinavian name describing a “descendant of the ancestors.”
  55. Olaga – a sweet Samoan boy’s name meaning “life.”
  56. Olan – many male names that start with O come from Scandinavia – Olan means “ancestor’s heir.”
  57. Olar – some Norwegian male names have the strangest meanings, like Olar, meaning “green beast.”
  58. Olavo – this short and sweet Portuguese and Spanish name means “descendant of” and “ancestor’s relic.”
  59. Ole – is of Danish and Norwegian origin, meaning “ancestor’s descendant.”
  60. Oleg – this Slavic boy’s name is common in Russia, Belarus, and Ukraine and means “blessed.”
  61. Oleksander – a Ukrainian version of the Greek Alexander, meaning “defender of humankind.”
  62. Oleksei – this Ukrainian name derives from ancient Greek and means “guard, protect, and defend.”
  63. Olexei – a variant of Aleksei, derived from the Greek Alexander, meaning “defender of humankind.”
  64. Ollie – a cool nickname for Oliver, with the same meaning.
  65. Olimpio – an edgy Greek boy’s name meaning “pertaining to Mount Olympus.”
  66. Olivander – this English, Germanic, and Greek name means “protector of the olive tree.”
  67. Oliver – is the masculine version of Olive, meaning “olive tree” in Greek.
  68. Olivero – an Old Italian form of Oliver meaning “olive tree.”
  69. Olivier – is the lovely French version of Oliver.
  70. Olivor – you guessed it – a variant of the Greek Oliver with the same meaning and origin.
  71. Olson – of Norse origin and means “son of Olaf” and “ancestor and heir.”
  72. Olympios – meaning “of Mount Olympus,” this Greek name is steeped in mythology.
  73. Olympus – possibly meaning “from Mount Olympus” or “home of the gods” in Greek.
  74. Omar – a top Arabic and Muslim name meaning “flourishing and long life.”
  75. Omario – this posh name means “eloquent and articulate” and hails from Jamaica.
  76. Omega – the last letter of the Greek alphabet, Omega means “the end.”
  77. Omid – the first Persian boy’s name to hit the list, meaning hope.
  78. Omotunde – this sweet and meaningful Nigerian boy’s name means “the child has returned.”
  79. Ondrei – of Greek and French origin, meaning “man or warrior.”
  80. Onfre – a derivative of the Spanish name Onofre, meaning “peace and warrior.”
  81. Onjel – derived from the Latin Angelus, meaning “messenger of God.”
  82. Onofredo – a long form of Onfre, meaning “peaceful warrior” in German and Spanish.
  83. Onofrius – possibly Italian or German, meaning “defender of peace.”
  84. Onorato – derived from the Latin Honoratus, meaning “honorable.”
  85. Onslow – of British and Arabic origin, meaning “enthusiast’s hill” or “hill of the passionate one.”
  86. Onyx – a unisex English name describing a “black gemstone.”
  87. Oratio – this Italian boy’s name has a beautiful aesthetic and means “prayer.”
  88. Orford – is of Old English origin, meaning “ford of cattle.”
  89. Orhan – some names that start with O are Turkish – Orhan means “great leader.”
  90. Oriel – a brilliant Latin name for precious children, meaning “golden.”
  91. Orion – this classic Greek boy’s name means “great hunter, dawning, and rising in the sky.”
  92. Orkins – derived from the Yiddish male name Orke of unknown meaning.
  93. Orlando – an Italian variant of Roland, meaning “fame of the land” or “famous land.”
  94. Ormon – is possibly of Irish descent, meaning “red, spear protector,” or “ship protector.”
  95. Ormond – a variant of Ormon, meaning “red and spear protector” in Gaelic.
  96. Ormondo – this French and Old English name means “mountain of bears.”
  97. Ornet – here’s a cool Old English and French name meaning “little eagle.”
  98. Orric – associated with strength, this Old English name means “oak tree.”
  99. Ors – with roots in Old French, Ors means “hero.”
  100. Orsen – the Latin form of Orson, meaning “a bear.”
  101. Orsin – this unique French and Latin name means “bear cub.”
  102. Orsini – this Italian name derives from the Latin “ursinus” and means “bear-like.”
  103. Orson – similar to Orsin, this French and Latin name means “bear cub.”
  104. Orsonio – continuing the Latin “bear” theme, this Spanish/Hispanic name is similar to Orsen.
  105. Orvelle – in an English version of Orville, meaning “golden town.”
  106. Orville – an invented English name from literature, meaning “golden town.”
  107. Orwell – a famous Anglo-Saxon place name, meaning “the branch of the river.”
  108. Orwynne – an unusual English/Scottish name meaning “from Irving.”
  109. Osage – this Native American Indian name means “people of the middle waters.”
  110. Osborne – derived from the Old Norse Asbjorn, meaning “divine bear” or “god bear.”
  111. Osbourne – an alternative spelling of Osborne with the same meaning and origin.
  112. Oscar – is of Irish origin, meaning “God spear, champion warrior, and deer-lover.”
  113. Oshea – a Hebrew variant of Hosea and Joshua, meaning “to save.”
  114. Osier – is derived from Old French and describes someone “living near a willow tree or grove.”
  115. Osip – this quirky Hebrew name means “God will multiply.”
  116. Osiris – many names for boys that start with O are Greek – Osiris means “powerful and mighty.”
  117. Oslo – the Norwegian capital with an uncertain meaning of “meadow at the foot of the hill.”
  118. Osment – derived from the Old Norse Ásmundr, meaning “God’s protection.”
  119. Osmond – similar to Osment, this English name means “God’s protector.”
  120. Osmont – this English child’s name means “divine protector.”
  121. Osred – derived from the Old English Osræd, meaning “God’s counsel.”
  122. Osrick – a regal Old English name meaning “divine ruler.”
  123. Ossin – surprisingly, this unusual name is Irish and means “little dear.”
  124. Ostin – a French variant of Austin, meaning “great and magnificent.”
  125. Ostynn – of French and Latin origin, meaning “great, magnificent, exalted, and venerable.”
  126. Osvald – derived from the Old Norse Osvaldr, this Spanish/English version means “divine ruler.”
  127. Oswald – taken from the Old English “os” and “weald,” meaning “divine power.”
  128. Oswinn – this Old English moniker means “God’s friend.”
  129. Osyka – of Native American Choctaw origin, meaning “eagle.”
  130. Oszkar – a Hungarian version of the Irish Oscar, meaning “little deer” or “deer-lover.”
  131. Otakar – the first Slovak name on the list and means “one who is watchful of wealth.”
  132. Otess – of Old English and German origin, meaning “son of Otto.”
  133. Otildo – related to the German name Odilo, meaning “prosperous in battle.”
  134. Otis – in Old English, Otis means “son of Ode, and “wealth” in German.
  135. Otley – this Old English placename possibly means “Otto’s woodland clearing.”
  136. Otmar – derived from the German Audemar, meaning “wealth and prosperity.”
  137. Otokar – this beautiful Czech name derives from Odoacer, meaning “wealthy and watchful.”
  138. Ottfrid – an alternate of the Old German Ottfried, meaning “wealthy peace.”
  139. Ottfried – from the Old German “ot,” meaning “wealth,” and “fridu,” meaning “peace.”
  140. Ottild – this unisex German name means “prospers in battle.”
  141. Ottman – another powerful Old German name meaning “wealthy man.”
  142. Otto – sticking with “wealthy” German names, Otto is a classic.
  143. Ottorino – the Italian version of Otto, meaning “wealth and fortune.”
  144. Ounslow – possibly derived from the Old English place Hounslow, meaning “hound’s mound.”
  145. Ousama – an Arabic respelling of Asama, meaning “lion-like.”
  146. Ovadiah – one of the many Hebrew variations of Obadiah, meaning “servant of God.”
  147. Owain – this ancient Old Welsh name means “wellborn.”
  148. Owen – an Old English variant of the Welsh Owain, meaning “young warrior, wellborn, and noble.”
  149. Oxford – an unusual boy’s name, Oxford means “ford where cattle cross.”
  150. Ozzie – this catchy German nickname for the country down under means “bear god” and “divine.”

Boy Names That Start With O FAQs

What Are the Coolest Boy Names That Start With O?

Selecting the coolest boy names that start with O is primarily subjective. Names like Ozzie, Owen, Oscar, Olson, and Ollie are trendy and fun, while Oakley, Oates, and Obi have an edgy feel that many parents like.

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About the Author

Mark Weir

Mark has always been fascinated by the stories behind names, their meanings, and the rich histories they carry. It's a curiosity that has grown into a full-fledged passion project, engaging him in the study of how names shape our identities and reflect our cultures. Since stepping away from his previous career, Mark has delved deeper into this fascinating realm. He spends his days unraveling these narratives and sharing his findings on Honey Name. He does all this amidst the tranquility of England's rivers and canals from his charming widebeam barge. His constant companions on this journey are his wife, Julie, and their adorable King Charles Cavalier, Eric.