O — Sixth Edition (1823)
393 articles
| Article | Vol | Words |
| OAK | 15 | 2,863 |
| OAKHAMPTON | 15 | 27 |
| OANNES | 15 | 72 |
| OAR | 15 | 256 |
| OARISTUS | 15 | 75 |
| OASIS | 15 | 28 |
| OAT | 15 | 179 |
| OATH | 15 | 3,361 |
| OATHLAW | 15 | 34 |
| OBADIAH | 15 | 245 |
| OBED-EDOM | 15 | 226 |
| OBELISK | 15 | 20 |
| OBELISKS | 15 | 628 |
| OBJECT | 15 | 45 |
| OBJECTION | 15 | 22 |
| OBJECTIVE | 15 | 30 |
| OBIT | 15 | 109 |
| OBLATE | 15 | 41 |
| OBLATI | 15 | 59 |
| OBLIGATION | 15 | 145 |
| OBLIQUE | 15 | 191 |
| OBLIQUUS | 15 | 21 |
| OBLONG | 15 | 14 |
| OBOLARIA | 15 | 23 |
| OBOLUS | 15 | 73 |
| OBOTH | 15 | 89 |
| OBREPTITIOUS | 15 | 22 |
| OBSCURE | 15 | 24 |
| OBSECRATION | 15 | 14 |
| OBSEQUIES | 15 | 7 |
| OBSERVATION | 15 | 19 |
| OBSERVATORY | 15 | 2,007 |
| OBSIDIANUS LAPIS | 15 | 8 |
| OBSIDIONALIS | 15 | 15 |
| OBSTETRICS | 15 | 8 |
| OBSTRUCTION | 15 | 30 |
| OBTURATOR | 15 | 6 |
| OBTUSE | 15 | 18 |
| OBY | 15 | 255 |
| OCCIDENT | 15 | 90 |
| OCCIPITAL | 15 | 17 |
| OCCULT | 15 | 113 |
| OCCULTATION | 15 | 26 |
| OCCUPANCY | 15 | 1,716 |
| OCCUPANT | 15 | 13 |
| OCCUPATION | 15 | 93 |
| OCEAN | 15 | 135 |
| OCEANIDES | 15 | 258 |
| OCEANUS | 15 | 212 |
| OCEIA | 15 | 109 |
| OCELLOT | 15 | 7 |
| OCHLOCRACY | 15 | 13 |
| OCHNA | 15 | 26 |
| OCHRE | 15 | 21 |
| OCHROMA | 15 | 23 |
| OCHUS | 15 | 177 |
| OCKLEY | 15 | 192 |
| OCRISIA | 15 | 14 |
| OCTAETERIS | 15 | 39 |
| OCTAGON | 15 | 47 |
| OCTAHEDRON | 15 | 17 |
| OCTANDRIA | 15 | 26 |
| OCTANT | 15 | 30 |
| OCTAPLA | 15 | 35 |
| OCTATEUCH | 15 | 12 |
| OCTAVIA | 15 | 527 |
| OCTAVIANUS | 15 | 835 |
| OCTOBER | 15 | 128 |
| OCTOSTYLE | 15 | 13 |
| OCULUS | 15 | 124 |
| OCZAKOW | 15 | 167 |
| ODA | 15 | 341 |
| ODDLY ODD | 15 | 35 |
| ODE | 15 | 12 |
| ODED | 15 | 245 |
| ODENSEE | 15 | 358 |
| ODENATUS | 15 | 293 |
| ODER | 15 | 91 |
| ODESSA | 15 | 196 |
| ODEUM | 15 | 63 |
| ODIN | 15 | 711 |
| ODIN'S FIRE | 15 | 259 |
| ODO | 15 | 146 |
| ODOACER | 15 | 249 |
| ODOMETER | 15 | 12 |
| ODONTALGIA | 15 | 6 |
| ODONTOIDE | 15 | 21 |
| ODOROUS | 15 | 24 |
| ODYSSEY | 15 | 456 |
| OECONOMICS | 15 | 33 |
| OECONOMISTS | 15 | 71 |
| OECONOMY | 15 | 67 |
| OECUMENICAL | 15 | 12 |
| OEDEMA | 15 | 367 |
| OEGWA | 15 | 393 |
| OELAND | 15 | 69 |
| OENANTHE | 15 | 25 |
| OENOPTAE | 15 | 7 |
| OENOS | 15 | 69 |
| OENOTHERA | 15 | 24 |
| OENOTRIA | 15 | 90 |
| OENOTRIDES | 15 | 47 |
| OESEL | 15 | 56 |
| OESOPHAGUS | 15 | 32 |
| OESTRUS | 15 | 13 |
| OETA | 15 | 166 |
| OETING | 15 | 133 |
| OFFA'S DYKE | 15 | 29 |
| OFFANTO | 15 | 48 |
| OFFENCE | 15 | 15 |
| OFFERINGS | 15 | 1,011 |
| OFFICE | 15 | 190 |
| OFFICER | 15 | 376 |
| OFFICIAL | 15 | 42 |
| OFFICINAL | 15 | 47 |
| OFFING | 15 | 78 |
| OFF-SETS | 15 | 49 |
| OGEE | 15 | 24 |
| OGHAMS | 15 | 150 |
| OGIVE | 15 | 76 |
| OGYGES | 15 | 49 |
| OGYGIA | 15 | 53 |
| OHIO | 15 | 394 |
| OIL | 15 | 73 |
| OISE | 15 | 86 |
| OKEHAM | 15 | 43 |
| OKINGHAM | 15 | 51 |
| OLAX | 15 | 1,717 |
| OLDENBURG | 15 | 951 |
| OLDENLANDIA | 15 | 220 |
| OLD-HEAD | 15 | 246 |
| OLD-WIFE | 15 | 99 |
| OLEA | 15 | 42 |
| OLEANDER | 15 | 16 |
| OLECRANUM | 15 | 28 |
| OLENUS | 15 | 75 |
| OLERON | 15 | 127 |
| OLEUM PALME CHRISTI | 15 | 24 |
| OLFACATORY NERVES | 15 | 6 |
| OLGA | 15 | 170 |
| OLIBANUM | 15 | 28 |
| OLIGARCHY | 15 | 15 |
| OLIO | 15 | 188 |
| OLISIPO | 15 | 94 |
| OLIVAREZ | 15 | 1,380 |
| OLIVE | 15 | 151 |
| OLIVET | 15 | 453 |
| OLIVETAN | 15 | 155 |
| OLIVIER | 15 | 300 |
| OLMUTZ | 15 | 96 |
| OLYMPIA | 15 | 1,874 |
| OLYMPIAD | 15 | 245 |
| OLYMPIAS | 15 | 320 |
| OLYMPIC GAMES | 15 | 1,663 |
| OLYMPUS | 15 | 185 |
| OLYRA | 15 | 23 |
| OMAR-EBN AL KHATTAB | 15 | 1,382 |
| OMB | 15 | 635 |
| OMBRE | 15 | 742 |
| OMBRIA | 15 | 19 |
| OMBRO | 15 | 34 |
| OMBROMETER | 15 | 80 |
| OMELET | 15 | 77 |
| OMEN | 15 | 2,070 |
| OMENTUM | 15 | 31 |
| OMER | 15 | 144 |
| OMOA | 15 | 1,658 |
| OMOPHAGIA | 15 | 165 |
| OMPHALE | 15 | 375 |
| OMPHALEA | 15 | 26 |
| OMPHALO-MESENTERIC | 15 | 59 |
| OMRAH | 15 | 481 |
| ONANIA | 15 | 765 |
| ONCA | 15 | 108 |
| ONEGA | 15 | 62 |
| ONEGLIA | 15 | 88 |
| ONEIROCRITICA | 15 | 181 |
| ONEIROCRITICS | 15 | 233 |
| ONI | 15 | 80 |
| ONGLEE | 15 | 28 |
| ONION | 15 | 14 |
| ONISCUS | 15 | 13 |
| ONKELOS | 15 | 542 |
| ONOCLEA | 15 | 16 |
| ONOMANCIA | 15 | 58 |
| ONOMATOPOEIA | 15 | 108 |
| ONONIS | 15 | 12 |
| ONOPORDUM | 15 | 23 |
| ONOSANDER | 15 | 69 |
| ONOSMA | 15 | 23 |
| ONTARIO | 15 | 30 |
| ONYCOMANCY | 15 | 70 |
| ONYX | 15 | 396 |
| OONELLA | 15 | 67 |
| OPACITY | 15 | 15 |
| OPAH | 15 | 9 |
| OPAL | 15 | 11 |
| OPALIA | 15 | 60 |
| OPARO | 15 | 147 |
| OPERA | 15 | 483 |
| OPERATION | 15 | 35 |
| OPHIDIUM | 15 | 32 |
| OPHIOLOGY | 15 | 16,857 |
| OPHIOMANCY | 15 | 61 |
| OPHIORHIZA | 15 | 50 |
| OPHIR | 15 | 4,861 |
| OPHIRA | 15 | 12 |
| OPHITES | 15 | 202 |
| OPHRYS | 15 | 45 |
| OPHTHALMIA | 15 | 25 |
| OPIATES | 15 | 455 |
| OPIUM | 15 | 37 |
| OPOBALSAMUM | 15 | 28 |
| OPOCALPASUM | 15 | 55 |
| OPOPONAX | 15 | 19 |
| OPORTO | 15 | 133 |
| OPOSSUM | 15 | 8 |
| OPOUN | 15 | 201 |
| OPPENHEIM | 15 | 38 |
| OPPIANUS | 15 | 55 |
| OPPILATION | 15 | 30 |
| OPTATIVE MOOD | 15 | 49 |
| OPTIC ANGLE | 15 | 24 |
| OPTIC AXIS | 15 | 22 |
| OPTICS | 15 | 145,174 |
| OPTIMATES | 15 | 157 |
| OPTIO | 15 | 107 |
| OPTION | 15 | 141 |
| OPUNTIA | 15 | 423 |
| ORACH | 15 | 5 |
| ORACLE | 15 | 3,639 |
| ORAL | 15 | 21 |
| ORAN | 15 | 112 |
| ORANGE | 15 | 1,472 |
| ORATOR | 15 | 556 |
| ORATORIO | 15 | 240 |
| ORATORY | 15 | 114,555 |
| ORB | 15 | 9,726 |
| ORDINARY | 15 | 429 |
| ORDINATES | 15 | 30 |
| ORDINATION | 15 | 468 |
| ORDNANCE | 15 | 1,679 |
| ORDONNANCE | 15 | 170 |
| ORDOVICES | 15 | 24 |
| ORE | 15 | 287 |
| ORES | 15 | 40,576 |
| ORELLANA | 15 | 127 |
| ORENSE | 15 | 49 |
| ORESTES | 15 | 1,025 |
| ORFA | 15 | 82 |
| ORFFYREUS'S WHEEL | 15 | 324 |
| ORFORD | 15 | 261 |
| ORGAN | 15 | 5,063 |
| ORGASM | 15 | 79 |
| ORGIA | 15 | 110 |
| ORGUES | 15 | 179 |
| ORIBASIA | 15 | 23 |
| ORIBASUS | 15 | 72 |
| ORICHALCUM | 15 | 1,546 |
| ORIFICE | 15 | 11 |
| ORIGANUM | 15 | 26 |
| ORIENT | 15 | 78 |
| ORIGEN | 15 | 1,995 |
| ORIGENIANS | 15 | 133 |
| ORIGENISTS | 15 | 124 |
| ORIGINAL | 15 | 91 |
| ORIGUELA | 15 | 84 |
| ORILLON | 15 | 40 |
| ORIOLES | 15 | 15 |
| ORION | 15 | 919 |
| ORISTAGNI | 15 | 35 |
| ORKNEY ISLANDS | 15 | 7,688 |
| ORLEANS | 15 | 317 |
| ORLOPE | 15 | 34 |
| ORMOND | 15 | 83 |
| ORMSIDE | 15 | 36 |
| ORMSKIRK | 15 | 130 |
| ORMUS | 15 | 226 |
| ORNE | 15 | 161 |
| ORNITHOGALLUM | 15 | 26 |
| ORNITHOLOGY | 15 | 106,176 |
| ORNITHOMANCY | 15 | 18 |
| ORNITHOPUS | 15 | 23 |
| ORNITHORYNCHUS PARADOXUS | 15 | 41 |
| ORNUS FRAXINUS | 15 | 25 |
| OROBANCHE | 15 | 23 |
| OROBIO | 15 | 2,943 |
| ORPHEUS | 15 | 2,136 |
| ORPIMENT | 15 | 55 |
| ORRERY | 15 | 119 |
| ORTEGAL | 15 | 24 |
| ORTELIUS | 15 | 139 |
| ORTHEZ | 15 | 165 |
| ORTHODOX | 15 | 67 |
| ORTHOGRAPHY | 15 | 131 |
| ORTHOPNOEA | 15 | 34 |
| ORTIVE | 15 | 40 |
| ORTNAU | 15 | 84 |
| ORTOLAN | 15 | 5 |
| ORTYGIA | 15 | 158 |
| ORVIETO | 15 | 786 |
| OSCHOPHORIA | 15 | 476 |
| OSCILLA | 15 | 123 |
| OSENLEY-ISLAND | 15 | 55 |
| OSIRIS | 15 | 1,252 |
| OSMUNDA | 15 | 13 |
| OSNABURG | 15 | 1,110 |
| OSORIUS | 15 | 672 |
| OSSA | 15 | 140 |
| OSSAT | 15 | 176 |
| OSSIAN | 15 | 9,490 |
| OSSIFICATION | 15 | 535 |
| OSSORY | 15 | 12 |
| OSSUNA | 15 | 28 |
| OSTADE | 15 | 177 |
| OSTALRIC | 15 | 26 |
| OSTEND | 15 | 271 |
| OSTEOCOLLA | 15 | 857 |
| OSTEOLOGY | 15 | 13 |
| OSTERVALD | 15 | 115 |
| OSTIA | 15 | 361 |
| OSTIACKS | 15 | 641 |
| OSTRACION | 15 | 13 |
| OSTRACISM | 15 | 1,304 |
| OSTRACITES | 15 | 75 |
| OSTREA | 15 | 17 |
| OSTROVIZZA | 15 | 109 |
| OSTUNI | 15 | 50 |
| OSWEGO | 15 | 35 |
| OSWEIZEN | 15 | 40 |
| OSWESTRY | 15 | 417 |
| OSYMANDES | 15 | 647 |
| OTACOUSTIC INSTRUMENT | 15 | 11 |
| OTAHEITE | 15 | 16,257 |
| OTAGIA | 15 | 5 |
| OTELANDS | 15 | 271 |
| OTHNIEL | 15 | 370 |
| OTHO | 15 | 941 |
| OTHONNA | 15 | 23 |
| OTHRYADES | 15 | 112 |
| OTIS | 15 | 13 |
| OTLEY | 15 | 145 |
| OTODINI | 15 | 268 |
| OTRANTO | 15 | 533 |
| OTRICOLI | 15 | 137 |
| OTTER | 15 | 9 |
| OTTERBURN | 15 | 87 |
| OTTERY | 15 | 144 |
| OTWAY | 15 | 577 |
| OVAL | 15 | 87 |
| OVARIUM | 15 | 32 |
| OVATION | 15 | 315 |
| OUDENARDE | 15 | 189 |
| OVEN | 15 | 107 |
| OVERALL | 15 | 616 |
| OVERBURY | 15 | 670 |
| OVERHANDLING | 15 | 50 |
| OVERSMAN | 15 | 26 |
| OVERT | 15 | 30 |
| OVERTURE | 15 | 55 |
| OVERYSSEL | 15 | 168 |
| OVIEDA | 15 | 86 |
| OUGHTRED | 15 | 351 |
| OVID | 15 | 1,078 |
| OVIEDO | 15 | 302 |
| OVILIA | 15 | 103 |
| OVIPAROUS | 15 | 17 |
| OVIS | 15 | 17 |
| OUNCE | 15 | 53 |
| OVOLO | 15 | 46 |
| OU-POEY-TSE | 15 | 720 |
| OUSTER | 15 | 182 |
| OUSTIOUG | 15 | 109 |
| OUT-POSTS | 15 | 24 |
| OUTLAW | 15 | 95 |
| OUTLAWRY | 15 | 3,425 |
| OWLING | 15 | 247 |
| OXALIS | 15 | 24 |
| OXFORD | 15 | 2,380 |
| OXFORDSHIRE | 15 | 262 |
| OXGANG | 15 | 25 |
| OXUS | 15 | 100 |
| OXYCRATE | 15 | 187 |
| OXYGEN | 15 | 77 |
| OXYGLYCU | 15 | 70 |
| OXYMEL | 15 | 8 |
| OYER | 15 | 44 |
| OYSTER | 15 | 12 |
| OYSTERS | 15 | 166 |
| OZANAM | 15 | 322 |
| OZELL | 15 | 109 |
| OZIAS | 15 | 195 |
| OZOL | 15 | 604 |