150 Boy Names That Start With O, From Oak to Ozzie

The letter O gives a name that lovely round, open sound, think Oliver and Owen, Osiris and Otto, names that feel warm on the tongue and a little bit grand.

This list gathers 150 boy names that start with O, pulled from all over the map: sturdy English classics, Irish and Scandinavian picks, biblical choices, and a few rare finds you will not hear on every playground. Origins and quick meanings sit right beside each one.

Scroll through and see which O name fits the little guy you are naming.

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

Here are 150 unique and classic O names for boys to consider.

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: A regal Yoruba name from Nigeria, Oba means “king” and serves as a royal title for traditional rulers.
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: A Yoruba name from Nigeria, Obafemi means “the king loves me.”
10. Obama: A Luo name from Kenya meaning “crooked” or “slightly bending,” known worldwide through President Barack Obama.
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 languages, meaning “descendant of Brian.”
17. Oceanus: A rare Greek male name meaning “of the ocean.”
18. Ochs: 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, meaning “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,” referring to a plant used in dye.
23. Odd: A Scandinavian name still used in Norway, Odd means “point of a blade” or “arrow tip.”
24. Odean: In Jamaica, it means “advisor,” and in Irish, it translates to “descendant of the deacon.”
25. Odell: Derived from the Old English “woad hill,” referring to 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: A lovely Irish choice, Odhran means “little pale-green one.”
29. Odie: A shortened nickname derived from Odell, meaning “woad hill.”
30. Odilo: Borne by Saint Odilo, a medieval abbot of Cluny, this German name means “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: A strong English option, Ogdan means “from the oak valley.”
40. Ogden: An alternate spelling of the Old English Ogdan, meaning “from the oak valley.”
41. Ogun: In Yoruba belief, Ogun is the orisha of iron, war, and metalwork, a powerful and protective figure.
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: Of Greek and French origin, Ohndre means “man or warrior.”
46. Ohnjel: This six-letter unisex Greek name means “messenger of God.”
47. Ohtli: A gender-neutral Aztec name meaning “road or path.”
48. Oisin: This rare five-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: A rare name of Japanese origin, said to mean “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: A Scandinavian name, Olan means “ancestor’s heir” or “descendant.”
57. Olar: A Norwegian name, Olar is said to mean “green beast.”
58. Olavo: This short and sweet Portuguese and Spanish name means “descendant of” and “ancestor’s relic.”
59. Ole: 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, carrying the exact 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: From the Latin for “olive tree,” a symbol of peace, Oliver ranked third for US boys in 2024.
68. Olivero: An Old Italian form of Oliver meaning “olive tree.”
69. Olivier: The lovely French version of Oliver.
70. Olivor: 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 bold unisex name taken from the black gemstone, from a Greek word meaning “claw” or “nail.”
87. Oratio: This Italian boy’s name has a beautiful aesthetic and means “prayer.”
88. Orford: Of Old English origin, meaning “ford of cattle.”
89. Orhan: A Turkish name meaning “great leader,” borne by Orhan I, an early ruler of the Ottoman Empire.
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: 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: 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 and Hispanic name is similar to Orsen.
105. Orvelle: 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 and 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: 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: 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: The Egyptian god of the afterlife and rebirth, Osiris carries a sense of power and resurrection.
117. Oslo: The Norwegian capital with an uncertain meaning of “meadow at the foot of the hill.”
118. Osment: Derived from the Old Norse Asmundr, 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: An unusual Irish name meaning “little deer” or “fawn.”
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 and 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, meaning “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: A vintage German classic meaning “wealth” or “fortune,” once carried by Holy Roman Emperors and enjoying a modern comeback.
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.”

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