
IELTS VOCABULARY | LEARN ENGLISH | ENGLISH VOCABULARY
| Oaken | adv. | Made Of Or From Oak. |
| Oakum | n. | Hemp-Fiber Obtained By Untwisting And Picking Out Loosely The Yarns Of Old Hemp Rope. |
| Obdurate | adv. | Impassive To Feelings Of Humanity Or Pity. |
| Obelisk | n. | A Square Shaft With Pyramidal Top, Usually Monumental Or Commemorative. |
| Obese | adv. | Exceedingly Fat. |
| Obesity | n. | Excessive Fatness. |
| Obituary | adv. | A Published Notice Of A Death. |
| Objective | adv. | Grasping And Representing Facts As They Are. |
| Objector | n. | One Who Objects, As To A Proposition, Measure, Or Ruling. |
| Obligate | v. | To Hold To The Fulfillment Of Duty. |
| Obligatory | adv. | Binding In Law Or Conscience. |
| Oblique | adv. | Slanting; Said Of Lines. |
| Obliterate | v. | To Cause To Disappear. |
| Oblivion | n. | The State Of Having Passed Out Of The Memory Or Of Being Utterly Forgotte |
| Obsequies | n. | Funeral Rites. |
| Obsequious | adv. | Showing A Servile Readiness To Fall In With The Wishes Or Will Of Another. |
| Observance | n. | A Traditional Form Or Customary Act. |
| Observant | adv. | Quick To Notice. |
| Observatory | n. | A Building Designed For Systematic Astronomical Observations. |
| Obsolescence | n. | The Condition Or Process Of Gradually Falling Into Disuse. |
| Obsolescent | adv. | Passing Out Of Use, As A Word. |
| Obsolete | adv. | No Longer Practiced Or Accepted. |
| Obstetrician | n. | A Practitioner Of Midwifery. |
| Obstetrics | n. | The Branch Of Medical Science Concerned With The Treatment And Care Of Women During Pregnancy. |
| Obstinacy | n. | Stubborn Adherence To Opinion, Arising From Conceit Or The Desire To Have One’S Own Way. |
| Obstreperous | adv. | Boisterous. |
| Obstruct | v. | To Fill With Impediments So As To Prevent Passage, Either Wholly Or In Part. |
| Obstruction | n. | Hindrance. |
| Obtrude | v. | To Be Pushed Or To Push Oneself Into Undue Prominence. |
| Obtrusive | adv. | Tending To Be Pushed Or To Push Oneself Into Undue Prominence. |
| Obvert | v. | To Turn The Front Or Principal Side Of (A Thing) Toward Any Person Or Object. |
| Obviate | v. | To Clear Away Or Provide For, As An Objection Or Difficulty. |
| Occasion | n. | An Important Event Or Celebratio |
| Occident | n. | The Countries Lying West Of Asia And The Turkish Dominions. |
| Occlude | v. | To Absorb, As A Gas By A Metal. |
| Occult | adv. | Existing But Not Immediately Perceptible. |
| Occupant | n. | A Tenant In Possession Of Property, As Distinguished From The Actual Owner. |
| Occurrence | n. | A Happening. |
| Octagon | n. | A Figure With Eight Sides And Eight Angles. |
| Octave | n. | A Note At This Interval Above Or Below Any Other, Considered In Relation To That Other. |
| Octavo | n. | A Book, Or Collection Of Paper In Which The Sheets Are So Folded As To Make Eight Leaves. |
| Octogenarian | adv. | A Person Of Between Eighty And Ninety Years. |
| Ocular | adv. | Of Or Pertaining To The Eye. |
| Oculist | n. | One Versed Or Skilled In Treating Diseases Of The Eye. |
| Oddity | n. | An Eccentricity. |
| Ode | n. | The Form Of Lyric Poetry Anciently Intended To Be Sung. |
| Odious | adv. | Hateful. |
| Odium | n. | A Feeling Of Extreme Repugnance, Or Of Dislike And Disgust. |
| Odoriferous | adv. | Having Or Diffusing An Odor Or Scent, Especially An Agreeable One. |
| Odorous | adv. | Having An Odor, Especially A Fragrant One. |
| Off | adv. | Farther Or More Distant. |
| Offhand Ad | v. | Without Preparation. |
| Officiate | v. | To Act As An Officer Or Leader. |
| Officious | adv. | Intermeddling With What Is Not One’S Concer |
| Offshoot | n. | Something That Branches Off From The Parent Stock. |
| Ogre | n. | A Demon Or Monster That Was Supposed To Devour Human Beings. |
| Ointment | n. | A Fatty Preparation With A Butter-Like Consistency In Which A Medicinal Substance Exists. |
| Olfactory | adv. | Of Or Pertaining To The Sense Of Smell. |
| Olive-Branch | n. | A Branch Of The Olive-Tree, As An Emblem Of Peace. |
| Ominous | adv. | Portentous. |
| Omission | n. | Exclusio |
| Omnipotence | n. | Unlimited And Universal Power. |
| Omnipotent | adv. | Possessed Of Unlimited And Universal Power. |
| Omniscience | n. | Unlimited Or Infinite Knowledge. |
| Omniscient | adv. | Characterized By Unlimited Or Infinite Knowledge. |
| Omnivorous | adv. | Eating Or Living Upon Food Of All Kinds Indiscriminately. |
| Onerous | adv. | Burdensome Or Oppressive. |
| Onrush | n. | Onset. |
| Onset | n. | An Assault, Especially Of Troops, Upon An Enemy Or Fortificatio |
| Onslaught | n. | A Violent Onset. |
| Onus | n. | A Burden Or Responsibility. |
| Opalescence | n. | The Property Of Combined Refraction And Reflection Of Light, Resulting In Smoky Tints. |
| Opaque | adv. | Impervious To Light. |
| Operate | v. | To Put In Action And Supervise The Working Of. |
| Operative | adv. | Active. |
| Operator | n. | One Who Works With Or Controls Some Machine Or Scientific Apparatus. |
| Operetta | n. | A Humorous Play In Dialogue And Music, Of More Than One Act. |
| Opinion | n. | A Conclusion Or Judgment Held With Confidence, But Falling Short Of Positive Knowledge. |
| Opponent | n. | One Who Supports The Opposite Side In A Debate, Discussion, Struggle, Or Sport. |
| Opportune | adv. | Especially Fit As Occurring, Said, Or Done At The Right Moment. |
| Opportunist | n. | One Who Takes Advantage Of Circumstances To Gain His Ends. |
| Opportunity | n. | Favorable Or Advantageous Chance Or Opening. |
| Opposite | adv. | Radically Different Or Contrary In Action Or Movement. |
| Opprobrium | n. | The State Of Being Scornfully Reproached Or Accused Of Evil. |
| Optic | n. | Pertaining To The Eye Or Visio |
| Optician | n. | One Who Makes Or Deals In Optical Instruments Or Eye-Glasses. |
| Optics | n. | The Science That Treats Of Light And Vision, And All That Is Connected With Sight. |
| Optimism | n. | The View That Everything In Nature And The History Of Mankind Is Ordered For The Best. |
| Option | n. | The Right, Power, Or Liberty Of Choosing. |
| Optometry | n. | Measurement Of The Powers Of Visio |
| Opulence | n. | Affluence. |
| Opulent | adv. | Wealthy. |
| Oral | adv. | Uttered Through The Mouth. |
| Orate | v. | To Deliver An Elaborate Or Formal Public Speech. |
| Oration | n. | An Elaborate Or Formal Public Speech. |
| Orator | n. | One Who Delivers An Elaborate Or Formal Speech. |
| Oratorio | n. | A Composition For Solo Voices, Chorus, And Orchestra, Generally Taken From The Scriptures. |
| Oratory | n. | The Art Of Public Speaking. |
| Ordeal | n. | Anything That Severely Tests Courage, Strength, Patience, Conscience, Etc. |
| Ordinal | n. | That Form Of The Numeral That Shows The Order Of Anything In A Series, As First, Second, Third. |
| Ordination | n. | A Consecration To The Ministry. |
| Ordnance | n. | A General Name For All Kinds Of Weapons And Their Appliances Used In War. |
| Orgies | n. | Wild Or Wanton Revelry. |
| Origin | n. | The Beginning Of That Which Becomes Or Is Made To Be. |
| Original | adv. | Not Copied Nor Produced By Imitatio |
| Originate | v. | To Cause Or Constitute The Beginning Or First Stage Of The Existence Of. |
| Ornate | adv. | Ornamented To A Marked Degree. |
| Orthodox | adv. | Holding The Commonly Accepted Faith. |
| Orthodoxy | n. | Acceptance Of The Common Faith. |
| Orthogonal | adv. | Having Or Determined By Right Angles. |
| Orthopedic | adv. | Relating To The Correcting Or Preventing Of Deformity |
| Orthopedist | n. | One Who Practices The Correcting Or Preventing Of Deformity |
| Oscillate | v. | To Swing Back And Forth. |
| Osculate | v. | To Kiss. |
| Ossify | v. | To Convert Into Bone. |
| Ostentation | n. | A Display Dictated By Vanity And Intended To Invite Applause Or Flattery. |
| Ostracism | n. | Exclusion From Intercourse Or Favor, As In Society Or Politics. |
| Ostracize | v. | To Exclude From Public Or Private Favor. Ought |
| Out-And-Out Ad | v. | Genuinely. |
| Outbreak | n. | A Sudden And Violent Breaking Forth, As Of Something That Has Been Pent Up Or Restrained. |
| Outburst | n. | A Violent Issue, Especially Of Passion In An Individual. |
| Outcast | n. | One Rejected And Despised, Especially Socially. |
| Outcry | n. | A Vehement Or Loud Cry Or Clamor. |
| Outdo | v. | To Surpass. |
| Outlandish | adv. | Of Barbarous, Uncouth, And Unfamiliar Aspect Or Actio |
| Outlast | v. | To Last Longer Than. |
| Outlaw | n. | A Habitual Lawbreaker. |
| Outlive | v. | To Continue To Exist After. |
| Out-Of-The-Way | adv. | Remotely Situated. |
| Outpost | n. | A Detachment Of Troops Stationed At A Distance From The Main Body To Guard Against Surprise. |
| Outrage | n. | A Gross Infringement Of Morality Or Decency. |
| Outrageous | adv. | Shocking In Conduct. |
| Outreach | v. | To Reach Or Go Beyond. |
| Outride | v. | To Ride Faster Than. |
| Outrigger | n. | A Part Built Or Arranged To Project Beyond A Natural Outline For Support. |
| Outright Ad | v. | Entirely. |
| Outskirt | n. | A Border Regio |
| Outstretch | v. | To Extend. |
| Outstrip | v. | To Go Beyond. |
| Outweigh | v. | To Surpass In Importance Or Excellence. |
| Overdo | v. | To Overtax The Strength Of. |
| Overdose | n. | An Excessive Dose, Usually So Large A Dose Of A Medicine That Its Effect Is Toxic. |
| Overeat | v. | To Eat To Excess. |
| Overhang | n. | A Portion Of A Structure Which Projects Or Hangs Over. |
| Overleap | v. | To Leap Beyond. |
| Overlord | n. | One Who Holds Supremacy Over Another. |
| Overpass | v. | To Pass Across Or Over, As A River. |
| Overpay | v. | To Pay Or Reward In Excess. |
| Overpower | v. | To Gain Supremacy Or Victory Over By Superior Power. |
| Overproduction | n. | Excessive Productio |
| Overreach | v. | To Stretch Out Too Far. |
| Overrun | v. | To Infest Or Ravage. |
| Oversee | v. | To Superintend. |
| Overseer | n. | A Supervisor. |
| Overshadow | v. | To Cast Into The Shade Or Render Insignificant By Comparison. |
| Overstride | v. | To Step Beyond. |
| Overthrow | v. | To Vanquish An Established Ruler Or Government. |
| Overtone | n. | A Harmonic. |
| Overture | n. | An Instrumental Prelude To An Opera, Oratorio, Or Ballet. |
| Overweight | n. | Preponderance. |



