560 American names begin with O, ordered by how many people have carried each one since 1880. See them split by girls and boys.
| Name | Meaning | 2025 births | |
|---|---|---|---|
| Olivia | Olive tree; peace | 13,554 | |
| Oliver | Olive tree; elf army | 14,963 | |
| Owen | Noble born; youth | 7,223 | |
| Oscar | millennial-parent name | 1,620 | |
| Omar | millennial-parent name | 1,333 | |
| Opal | Edwardian name | 740 | |
| Olive | current name | 1,604 | |
| Olga | Edwardian name | 50 | |
| Otis | interwar name | 422 | |
| Ollie | Edwardian name | 287 | |
| Orlando | Gen X and millennial name | 275 | |
| Ora | Edwardian name | 40 | |
| Otto | Wealth; prosperity | 1,241 | |
| Orville | interwar name | 14 | |
| Ola | interwar name | 13 | |
| Oakley | current name | 2,621 | |
| Ophelia | current name | 1,183 | |
| Octavia | current name | 982 | |
| Orion | current name | 1,030 | |
| Odell | interwar name | 23 | |
| Odessa | interwar name | 193 | |
| Osvaldo | millennial-parent name | 130 | |
| Omari | current name | 404 | |
| Odin | current name | 604 | |
| Oaklynn | current name | 1,973 | |
| Octavio | millennial-parent name | 154 | |
| Olin | interwar name | 86 | |
| Oma | Edwardian name | — | |
| Oren | current name | 174 | |
| Ofelia | interwar name | 87 | |
| Omer | Edwardian name | 70 | |
| Onyx | current name | 1,036 | |
| Odis | interwar name | 15 | |
| Ocean | current name | 720 | |
| Ona | Edwardian name | 21 | |
| Orval | Edwardian name | — | |
| Otha | interwar name | — | |
| Olen | interwar name | 33 | |
| Ocie | Edwardian name | 20 | |
| Oaklee | current name | 640 | |
| Orin | interwar name | 85 | |
| Orrin | Edwardian name | 62 | |
| Orpha | Edwardian name | — | |
| Oswaldo | millennial-parent name | 41 | |
| Oralia | midcentury name | 12 | |
| Oleta | interwar name | — | |
| Oaklyn | current name | 479 | |
| Ouida | interwar name | — | |
| Ottis | interwar name | 15 | |
| Ossie | Edwardian name | — | |
| Ozzy | current name | 618 | |
| Osiris | current name | 215 | |
| Oran | interwar name | 19 | |
| Obie | interwar name | 10 | |
| Oswald | Edwardian name | 67 | |
| Odette | current name | 303 | |
| Odie | Edwardian name | 17 | |
| Ozzie | current name | 164 | |
| Oakleigh | current name | 423 | |
| Obed | millennial-parent name | 72 | |
| Omarion | millennial-parent name | 52 | |
| Osman | current name | 181 | |
| Oriana | millennial-parent name | 113 | |
| Octavius | Gen X and millennial name | 72 | |
| Olympia | Gen X and millennial name | 84 | |
| Odalys | Gen X and millennial name | 39 | |
| Otho | Edwardian name | — | |
| Osian | Little deer | 165 | |
| Oral | Edwardian name | — | |
| Oskar | current name | 93 | |
| Oneal | interwar name | 6 | |
| Osbaldo | millennial-parent name | 14 | |
| Omega | current name | 32 | |
| Osiel | current name | 123 | |
| Odelia | current name | 56 | |
| Ozell | interwar name | 5 | |
| Olan | interwar name | 14 | |
| Oziel | current name | 229 | |
| Orson | current name | 126 | |
| Odalis | Gen X and millennial name | 11 | |
| Olyvia | millennial-parent name | 48 | |
| Olaf | Edwardian name | 5 | |
| Obadiah | current name | 104 | |
| Ozella | interwar name | 7 | |
| Om | millennial-parent name | 66 | |
| Osmar | millennial-parent name | 59 | |
| Oneida | Edwardian name | — | |
| Ozie | interwar name | — | |
| Orie | interwar name | 11 | |
| Ole | Edwardian name | 21 | |
| Osie | interwar name | — | |
| Orland | interwar name | — | |
| Ozias | current name | 381 | |
| Onie | Edwardian name | — | |
| Olivier | millennial-parent name | 52 | |
| Oliva | Gen X and millennial name | 16 | |
| Ori | current name | 107 | |
| Olevia | interwar name | — | |
| Orvil | interwar name | — | |
| Oris | Edwardian name | — | |
| Ova | Edwardian name | — | |
| Ottie | Edwardian name | — | |
| Oona | current name | 62 | |
| Oneil | interwar name | 7 | |
| Osborne | Edwardian name | 22 | |
| Onnie | Edwardian name | — | |
| Oakland | current name | 208 | |
| Otilia | interwar name | 18 | |
| Orlin | interwar name | 22 | |
| Octavious | Gen X and millennial name | 17 | |
| Oda | Edwardian name | — | |
| Oden | current name | 74 | |
| Orla | current name | 70 | |
| Octavian | current name | 51 | |
| Oneta | interwar name | — | |
| Okey | interwar name | — | |
| Oliwier | millennial-parent name | 33 | |
| Orlaith | Golden princess | 65 | |
| Orianna | millennial-parent name | 53 | |
| Olene | interwar name | — | |
| October | current name | 49 | |
| Olivia-Rose | current name | 42 | |
| Oshea | current name | 54 | |
| Odilia | interwar name | 16 | |
| Oletha | interwar name | — | |
| Otelia | interwar name | — | |
| Omie | interwar name | — | |
| Onita | interwar name | — | |
| Oretha | interwar name | — | |
| Orvel | Edwardian name | — | |
| Oceana | millennial-parent name | 43 | |
| Orvin | Edwardian name | — | |
| Oryan | millennial-parent name | 36 | |
| Ottilie | current name | 57 | |
| Ovidio | current name | 24 | |
| Otoniel | Gen X and millennial name | 15 | |
| Olinda | midcentury name | — | |
| Oksana | Gen X and millennial name | 15 | |
| Orene | Edwardian name | — | |
| Onalee | interwar name | 8 | |
| Olie | interwar name | — | |
| Orelia | interwar name | 10 | |
| Orrie | Edwardian name | — | |
| Orris | Edwardian name | — | |
| Osama | Gen X and millennial name | 18 | |
| Orlan | interwar name | 7 | |
| Orvis | interwar name | — | |
| Omri | current name | 39 | |
| Orren | interwar name | 7 | |
| Orlo | Edwardian name | — | |
| Olena | current name | 21 | |
| Othel | interwar name | — | |
| Orman | interwar name | — | |
| Ontario | Gen X and millennial name | — | |
| Obinna | millennial-parent name | 16 | |
| Olean | interwar name | — | |
| Oneita | interwar name | — | |
| Ovie | Edwardian name | 9 | |
| Owyn | current name | 16 | |
| Odella | Edwardian name | 7 | |
| Orly | millennial-parent name | 29 | |
| Orian | current name | 20 | |
| Omayra | boomer-era name | — | |
| Ogden | Edwardian name | 9 | |
| Opie | current name | 29 | |
| Othello | Edwardian name | 8 | |
| Omid | Gen X and millennial name | 23 | |
| Ondrea | Gen X and millennial name | — | |
| Orlanda | boomer-era name | — | |
| Odile | Edwardian name | — | |
| Olivette | interwar name | 26 | |
| Oaklen | current name | 68 | |
| Odyssey | current name | 35 | |
| Osa | Edwardian name | 9 | |
| Oumar | millennial-parent name | 38 | |
| Oumou | millennial-parent name | 35 | |
| Oaklie | current name | 54 | |
| Owens | interwar name | 12 | |
| Ovid | Edwardian name | — | |
| Odean | interwar name | — | |
| Oluwatobi | millennial-parent name | 7 | |
| Oliviah | millennial-parent name | 9 | |
| Othniel | current name | 47 | |
| Ousmane | current name | 31 | |
| Othella | interwar name | — | |
| Orma | interwar name | — | |
| Orel | Edwardian name | 6 | |
| Onika | boomer-era name | 11 | |
| Octaviano | midcentury name | — | |
| Oz | current name | 33 | |
| Oak | current name | 59 | |
| Oralee | Edwardian name | — | |
| Orbie | Edwardian name | — | |
| Onna | current name | 12 | |
| Orlena | interwar name | — | |
| Ojas | current name | 46 | |
| Olivea | millennial-parent name | 7 | |
| Olajuwon | Gen X and millennial name | 8 | |
| Olivia-Grace | current name | 19 | |
| Orlagh | current name | 28 | |
| Odetta | interwar name | — | |
| Olando | boomer-era name | — | |
| Obert | interwar name | — | |
| Orange | interwar name | — | |
| Orva | Edwardian name | — | |
| Oziah | current name | 87 | |
| Olamide | millennial-parent name | 6 | |
| Osborn | interwar name | 6 | |
| Oval | interwar name | — | |
| Odessia | interwar name | — | |
| Oddie | Edwardian name | — | |
| Ottilia | Edwardian name | 13 | |
| Odessie | interwar name | — | |
| Odus | Edwardian name | — | |
| Onesimo | Gen X and millennial name | — | |
| Oluwadarasimi | current name | 19 | |
| Oslo | current name | 78 | |
| Oneda | interwar name | — | |
| Orlean | interwar name | — | |
| Olla | interwar name | — | |
| Orien | Edwardian name | 9 | |
| Osmin | millennial-parent name | 12 | |
| Overton | Edwardian name | — | |
| Othman | current name | 34 | |
| Odysseus | current name | 44 | |
| Olivia-Mae | current name | 19 | |
| Olden | Edwardian name | — | |
| Ormond | Edwardian name | — | |
| Oisin | current name | 22 | |
| Orli | current name | 22 | |
| Otila | interwar name | — | |
| Ohana | current name | 40 | |
| Ociel | millennial-parent name | 17 | |
| Olsen | current name | 66 | |
| Omarr | Gen X and millennial name | — | |
| Oswin | current name | 14 | |
| Obrian | Gen X and millennial name | — | |
| Olliver | current name | 24 | |
| Orhan | current name | 92 | |
| Olvin | current name | 21 | |
| Omero | Gen X and millennial name | — | |
| Oceanna | millennial-parent name | 5 | |
| Ofilia | interwar name | — | |
| Osmond | current name | 13 | |
| Oleg | current name | 9 | |
| Oluwadamilola | millennial-parent name | 10 | |
| Ostin | current name | 23 | |
| Orley | Edwardian name | — | |
| Orbin | Edwardian name | — | |
| Oriel | current name | 24 |