[TOEFL iBT] Danh sách từ vựng – Vần O

OBDURATE

Hard-hearted; stubborn – an obdurate, unrepentant criminal.

Synonyms:adamant, unyielding, inflexible

Antonyms:submissive, docile, compliant

OBLIVIOUS

(noun: OBLIVION): Forgetful; absent-minded – walking oblivious of his surroundings.

Synonyms:unmindful, heedless, abstracted

OBSESSION

A persistent feeling, idea, activity, etc., which dominates a person; the state of being exclusively preoccupied by a fixed idea – Now that he has learned bowling, it has become his obsession.

Synonyms:mania, infatuation (a foolish passion), monomania

OBSOLETE

No longer in use – an obsolete word, not even included by most dictionaries.

Synonyms:archaic, antiquated

OBTRUSIVE

(verb: OBTRUDE): Thrusting oneself or itself into undue prominence – made himself obnoxiously obtrusive.

Synonyms:intrusive, aggressive

OBVIATE

To prevent, dispose of, or make unnecessary by appropriate actions – an act which obviated all objections.

Synonyms:preclude, forestall

OMNIPOTENT

All-powerful – an omnipotent despot.

ONUS

Burden; duty; obligation – bore the onus of his difficult office creditably.

OSTENSIBLE

Apparent; pretended – his ostensible, though not actual, purpose.

OSTRACIZE

To banish; to exclude from public favor or privileges – a former premier ostracized by popular vote.

Synonym: outlaw