Here you will find English Opposite / Antonym Word List start with O.
1) Word :-
Obey : I always obey my father.
Opposite word :-
Disobey : One of my friend always disobeyed traffic rules.
2) Word :-
Oblige : Amit is always ready to oblige his friends.
Opposite word :-
Disoblige : I do not want to disoblige her parents by spending the night at their home.
3) Word :-
Observe : I observed the experiment that we did in the class.
Opposite word :-
Ignore : They ignored my decisions.
4) Word :-
Obstruct : A big tree obstructed the street after the storm.
Opposite word :-
Clear : They cleared the road for the prime minister.
5) Word :-
Obtain : We somehow managed to obtain the information from our enemy.
Opposite word :-
Lose : They lose their house in the disaster.
6) Word :-
Ooze : The crowd on the street starts to ooze forward.
Opposite word :-
Speed : Some boys sped past us on their bikes.
7) Word :-
Open : The shop will open tomorrow.
Opposite word :-
Close : The market is closed today.
8) Word :-
Oppress : She was oppressed by a sense of failure.
Opposite word :-
Brighten : The sky brightened after the storm.
9) Word :-
Organize : They organized the party very well.
Opposite word :-
Disarrange : The wind disarranges my hair pretty badly.
10) Word :-
Output : This device can output a high pitch sound.
Opposite word :-
Input : I input the data in my computer.