Words with O

Obligating	the condition of being morally or legally bound to do something	IELTS Essays – Essay # 2
Onlookers	a non-participating observer; a spectator	IELTS Essays – Essay # 10
Opine	hold and state as one's opinion	IELTS Essays - Essay # 23
Opulence	great wealth or luxuriousness	IELTS Essays – Essay # 9
Ordeal	a very unpleasant and prolonged experience	IELTS Essays – Essay # 48
Outgrew	grew too big for	IELTS Speaking – Test # 7
Outweigh	be heavier, greater, or more significant than	IELTS Essays – Essay # 1
Overdue	not having arrived, happened, or been done by the expected time	IELTS Letters – Letter # 5
Overhyped	claimed exaggeratedly	IELTS Essays – Essay # 36
Overwhelming	very great in amount	IELTS Essays – Essay # 14