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speculate about (someone or something)

To conjecture, hypothesize, or make guesses about someone or something without having supporting or conclusive evidence. We've all been speculating about the mysterious man who moved into the house two doors down. It's certain to be a gamble, but until we try it, all we can do is speculate about how the product will do on the market.
See also: speculate

speculate in (something)

To buy or sell some asset, such as commodities, securities, property, etc., at a risk while hoping to gain a profit from short-term market fluctuations. My uncle made, then promptly lost, a fortune speculating in oil wells in the 1980s. You'd be a fool to speculate in dairy in today's market.
See also: speculate

speculate on (something)

To conjecture, hypothesize, or make guesses about something without having supporting or conclusive evidence. You can't just speculate on what effect this legislation will have on the country—you've got to have some concrete data to show it will work! Instead of spending your energy speculating on the future, you should focus on the present and do what makes you happy.
See also: on, speculate

speculate about someone or something

to make guesses about someone or something; to hypothesize about someone or something. I refuse to speculate about Sally. I don't presume to guess what she will do. We don't speculate about the future.
See also: speculate

speculate in something

to make risky business deals in the buying and selling of something. Jeff made a fortune speculating in cotton. I do not wish to speculate in anything. It is too risky.
See also: speculate

speculate on something

to make a hypothesis about something. I really don't want to speculate on what might happen next. Would you care to speculate on what might happen if you quit your job?
See also: on, speculate
References in classic literature ?
How could I speculate when I already have so much trouble in regulating my income?
The fate of the relinquished provinces which lay beyond the dead lines we could only speculate upon.
Managing women, the ornaments of their sex--women who order everything for everybody, and know so much better than any person concerned what is good for their neighbours, don't sometimes speculate upon the possibility of a domestic revolt, or upon other extreme consequences resulting from their overstrained authority.
The Bureau of Customs (BOC) is considering the ambush of deputy commissioner Arturo Lachica an 'isolated incident' as the agency's chief declined to speculate on the motives behind the murder.
We could also speculate they are about talking to trees or homeopathy.
For both seasoned traders and for complete novices that merely want to speculate and 'play' the fluctuating stock, currency and commodity markets, Yalla
Byline: Joe Calzaghe has refused to speculate about rumours he is dating his Strictly Come Dancing partner.
But I'm not going to speculate about one particular company and their decisions that have not yet been made.
named industry veteran Muhtar Kent to the newly created post of international operations president, but the company's chief executive said it was too early to speculate on whether Kent could be Coke's next CEO.
And that is why I will not take part in games about trying to speculate about this and that, thereby undermining the Prime Minister.
Researchers now speculate that maternal smoking during or after pregnancy may result in gastrointestinal (GI) dysregulation and thus increase the risk of infant colic.
Cowley has invited 17 eminent historians to speculate on how history might have been changed if certain events or conditions had not occurred or had occurred differently.
Although Boshcoff says he cannot speculate on the exact number of jobs these various projects will create, he says he is confident they will provide more local job opportunities.
I am aware there is no corroboration evidence such as film footage but I can't speculate what may happen.
The women speculate on the stone and who will move it for them so they can anoint the body.