| Word | Meaning | Occurrences |
|---|---|---|
| objurgo | to chide, scold | 3 |
| oblatio | offering, sacrifice | 118 |
| oblectamentum | pleasure, amusement | 1 |
| oblectatio | delight | 5 |
| oblecto | to delight, divert | 6 |
| obligatio | binding, entangling | 3 |
| obligo | to bind up, bandage | 6 |
| obliquus | slanting, oblique | 4 |
| oblivio | forgetting, forgetfulness | 30 |
| obliviosus | forgetful, oblivious | 2 |
| obliviscor | to forget | 125 |
| oblivium | forgetfulness, oblivion | 2 |
| obloquor | to speak against, interrupt | 1 |
| obmutesco | to become dumb, be silent | 14 |
| obnixe | with all one’s strength | 2 |
| obnoxius | liable to punishment, guilty | 7 |
| obolus | obol, small Greek coin | 5 |
| oborior | to arise, appear | 1 |
| oboth | Oboth | 3 |
| obrigesco | to stiffen | 2 |
| obrizus | refined, pure | 5 |
| obruo | to overwhelm, overthrow | 12 |
| obscuro | to darken, obscure | 24 |
| obscurus | dark, obscure | 10 |
| obsecratio | prayer, supplication | 29 |
| obsecro | to pray, implore | 135 |
| obsequium | compliance, obedience | 16 |
| obsequor | to comply, yield | 3 |
| observabilis | to be observed | 1 |
| observantia | observance | 1 |
| observatio | watching, observance | 11 |
| observo | to watch, observe | 94 |
| obses | hostage | 9 |
| obsideo | to besiege | 53 |
| obsidio | siege | 15 |
| obsigno | to seal, seal up | 2 |
| obsisto | to stand against, to oppose | 2 |
| obsordesco | to become dirty, be soiled | 1 |
| obstetrico | assist in childbirth | 3 |
| obstetrix | midwife | 6 |
| obstinatus | resolved, obstinate | 1 |
| obstringo | to shut in, confine | 1 |
| obstruo | to block, stop up | 8 |
| obstupefacio | to stun, astonish | 2 |
| obstupesco | to become senseless, to be astonished | 38 |
| obsurdesco | to become deaf | 1 |
| obtego | to cover over, cover up | 1 |
| obtempero | to comply, obey | 6 |
| obtendo | to spread before, stretch over | 1 |
| obtenebresco | to grow dark | 1 |
| obtenebro | to make dark, to darken | 6 |
| obtentus | pretense, pretext | 4 |
| obtero | to bruise, crush | 1 |
| obtestor | to call as a witness, protest | 1 |
| obtineo | to take hold of, possess | 74 |
| obtingo | to fall to the lot of, befall | 1 |
| obtundo | to blunt, weaken | 2 |
| obturatio | stopping up | 1 |
| obturo | to stop up, close | 13 |
| obumbratio | shadow, darkness | 2 |
| obumbro | to overshadow, shade | 16 |
| obviam | towards, to meet | 50 |
| obvio | to meet | 12 |
| obvius | in the way, so as to meet | 9 |
| obvolvo | to wrap up | 6 |
| occasio | occasion, opportunity | 28 |
| occasus | falling, going down | 24 |
| occidens | sunset, west | 49 |
| occidentalis | western, westerly | 24 |
| occido | to strike down, kill; to fall, go down | 449 |
| occisio | killing, slaughter | 21 |
| occludo | to shut up, close | 2 |
| occubitus | going down, setting | 3 |
| occulte | secretly | 12 |
| occulto | to hide, conceal | 13 |
| occultus | hidden, secret | 40 |
| occumbo | to fall, sink down | 16 |
| occupatio | seizing, occupying | 2 |
| occupo | to take possession of, to occupy | 38 |
| occurro | to run up to, meet | 111 |