obesity n. the condition of being obese; increased body weight caused by excessive accumulation of fat

objection n. opposition; appeal; denial; protest

objective adj. impartial; unbiased; existing outside of the mind; relating to or characteristic of a direct object (Grammar); expressing or dealing with facts

objective n. aim; purpose, goal; objective case (Grammar)

obligation n. duty responsibility; indebtedness; agreement

obligatory adj. binding; compelling; must be done; necessary

oblivious adj. lacking all memory; forgetful; lacking conscious awareness; unmindful

observe v. to watch; to study; to monitor; to supervise; to discern; to keep; to honor; to fulfill religious commandments; to follow; to abide by; to remark; to comment

obsolete adj. ancient; archaic; no longer in use; outdated; disappearing; useless

obtain v. to acquire; to come by; to procure; to secure; to earn; to achieve

obviate v. to anticipate and dispose of effectively; render unnecessary

obvious adj. clear; unmistakable; apparent; evident; plain

obviously adv. clearly; unmistakably; plainly; apparently

occasion n. opportunity; occurrence, event; incident; reason; cause; justification

occupancy n. period of residence; act of taking possession (Law); right of possession

occupation n. act of forcefully taking possession of an area; seizure; conquest; possession or settlement of land

occupied adj. conquered; seized; filled; taken up; in use (about a bathroom); inhabited; populated; absorbed, engrossed

occur v. to happen; to take place; to transpire; to come to mind; to suggest itself

occurrence n. happening; event; incident

offence n. attack; (Sports) side that pursues (rather than defends); misdeed; insult; state of being offended; transgression (also offense)

offender n. transgressor; person who breaks the law; one who insults

offense n. attack; (Sports) side that pursues (rather than defends); misdeed; insult; state of being offended; transgression (also offence)

offensive n. attack; act of aggression; position of pursuit or aggression

official n. person who holds public position; authority

offset n. outcome; compensation; counterbalance; printing method in which a printing plate transfers ink to a blanket which in turn transfers the ink to the paper (the plate does not directly touch the paper)

offset v. to compensate; to balance; to print with an offset printing press

omission n. deletion; negligence; failure; default

omit v. to delete; to skip over; to neglect

onus n. responsibility; duty; burden; impediment; blame

operate v. to act; to function; to manage; to use; to activate; to perform surgery

operation n. working, performance, handling; venture, undertaking; series of actions, procedure (e.g. mathematical operations); campaign; series of activities to achieve a goal (e.g. military operations); surgery

operational adj. working; functional; ready for use

operator n. one who activates; worker of a telephone switchboard; worker; operation symbol; character which signifies a logical or mathematical operation between several numbers (Computers)

opinion n. attitude; outlook; formal judgment or estimation

opportune adj. appropriate; fitting; well-timed; timely; proper; expedient

opportunity n. chance; occasion; favorable time to act

oppose v. to be in contention or conflict with; to be resistant to; to place opposite in contrast or counterbalance

opposite adj. facing, across from; contrary; reverse; different; antithetical

opposite adv. on or towards an opposite side; contrarily

opposite n. contrast; something contrary

oppositeprep. across from; facing

optimal adj. most favorable or desirable; optimum

option n. choice; alternative; possibility; selection; election

ordinary adj. regular; common

organize v. to arrange; to order; to systematize; to establish; to set up; to unite; to compile; to structure

origin n. source; beginning; birth; parentage; nationality

original adj. first; primary; innovative; creative; novel

original n. source from which something arises; originator; prototype; model; original work (as opposed to an imitation)

originality n. state of not being a derivative of anything else

originally adv. at first; in the first place; in a unique manner

originate v. to begin; to be created; to result from; to develop; to be born; to be produced

ostensible adj. apparent; seeming

ostentatious adj. showy; pretentious; bombastic; pompous; garish

outbound adj. leaving; sailing; traveling to another country

outdoor adj. of nature

outlet n. exit; means of relief (emotional, physical, etc.); electrical source for connecting appliances; store that sells products directly from the manufacturer (often at a discount); shop; joint; store

output n. yield; product; manufacture; information sent out from a computer (Computers)

outside adj. external; of the outdoors; from the outdoors; maximal

outstanding adj. excellent; conspicuous; prominent; notable; owing, due; unsettled (about a payment); unresolved

overall n. one piece garment made of trousers and a piece of cloth that covers the chest and has shoulder straps (originally worn to protect clothes while working)

overcome v. to subdue; to solve

overdraft n. limit to which money may be withdrawn from the bank on credit

overhaul n. an act of overhauling; a repair job

overhaul v. to examine or go over carefully for needed repairs; to dismantle in order to make repairs; to make extensive renovations or revisions on; renovate; to catch up with; overtake

overhead adj. of general expenses; general; positioned or directed over the head

overhead adv. from above; above; in the sky

overhead n. general expenses; manufacturing and business expenses; information which is attached to a message on a network in order to ensure error-free transmission to the correct destination (Computers)

overhear v. to hear (speech or someone speaking) without the speaker's awareness or intent

overlap v. to cover a part of; to have something in common

overlook v. to inspect; to supervise; to miss; to omit; to ignore; to excuse

overseas adj. beyond or across the sea; foreign

overseas adv. across the sea; from beyond the sea; over the sea

oversee v. to supervise; to manage; to inspect

overt adj. plain; clear; visible; public; intentional; undisguised (Law)

overtime adv. exceeding regular working hours; additional time (as in a sports game in order to break a tie score)

overtime n. work beyond regular working hours; pay for such work; extra time, additional time (as in a sports game in order to break a tie score)

overview n. synopsis; general survey; introduction

overwhelm v. to defeat; to master; to crush; to stagger; to stun; to daze; to flood; to engulf

owe v. to be indebted to; to be under obligation to pay or repay; to feel that a certain thing is deserved; to have an emotion or attitude toward someone or something

ownership n. legal right of possession