oppressive - Unjustly harsh or tyrannical, especially in the use of power or control.
opportune - Happening at a time that is convenient or likely to produce success.
obstinate - Stubbornly refusing to change one's behavior or ideas
outlandish - Foreign or unfamiliar, especially in a way that seems odd or eccentric.
outbreak - A sudden start or increase of something harmful, especially a disease or conflict.
optimize - To make the best and most effective use of a situation, opportunity, or resource.
orchestrate - To organize a complicated plan or event very carefully
operational - Something that is in working order and ready for use.
obfuscate - To make something less clear and harder to understand, especially if done deliberately.
ornery - Having an unpleasant mood or temper, likely to get angry and argue with people.
ostracize - To banish someone socially, making them feel isolated or unwanted.
offshoot - Something that has developed from something larger that already existed
