unknown quantity

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an unknown quantity

A person or thing that is unpredictable and thus difficult to anticipate. We're still revising our new product, so its potential success is an unknown quantity. This is her first year teaching, so her ability to connect with her students is still an unknown quantity.
See also: quantity, unknown

*unknown quantity

Fig. a person or thing about which no one is certain. (*Typically: be ~; become ~.) John is an unknown quantity. We don't know how he's going to act. The new clerk is an unknown quantity. Things may not turn out all right.
See also: quantity, unknown

unknown quantity

An unpredictable person or thing, as in We don't know how the new pitcher will do-he's an unknown quantity. This expression comes from algebra, where it signifies an unknown numerical value. Its figurative use dates from the mid-1800s.
See also: quantity, unknown

unknown quantity

a person or thing whose nature, value, or significance cannot be determined or is not yet known.
See also: quantity, unknown
References in periodicals archive ?
The Turks open against Brazil tomorrow and while Gunes has done his homework for that one he admits the other two nations - Costa Rica and China - are something of an unknown quantity.
ANOTHER unknown quantity for the Irish, although they will hardly be quaking in their boots at facing the Asian qualifiers - even though they did advance to the last 16 eight years ago in the United States where they were defeated by Sweden.
DESPITE SOME RECENT, heartening development--stateside distribution for two Tsai Ming-liang movies (Vive I'amour [1994] and The Hole [1998]) and Winstar's acquisition of an assortment of Hou Hsiao-hisens (including The Puppetmaster [1993] and Flowers of Shanghai [19981])--Taiwanese cinema is still an unknown quantity in America.
n Verdict: Miss Waters says: "Again they are very much an unknown quantity and for that reason I would not recommend them to patients.
It will be an advantage to see both the teams as they are an unknown quantity," he said.
Firefighters were called to make the vehicle safe and clear drains of the unknown quantity of milk that spilled onto the highway.
The raiders stole an unknown quantity of cigarettes as well as cash and a hard drive before leaving the store in an unknown direction.
The 19-year-old from Aachen is a bit of an unknown quantity having drawn his first contest staged in his hometown in May against 2-2-1 countryman Marcel Gottschalk.
BEST LONGSHOT A forecast outsider who could be primed to outrun its likely odds TOO MUCH TROUBLE is an unknown quantity but could provide an upset in the Group 3 Virgin Money Chester Vase (2.
The thirds took on an unknown quantity in the newly-formed St Margaret's Aigburth Staff side and were given a real test by a team with lots of potential but they edged home 25-13.
An unknown quantity of cash was also recovered, and is currently being tested by the forensics department.
At the start of this season he was an unknown quantity.
Boro remain something of an unknown quantity following mixed results in pre-season.
Thompson got the nod over other minor-league candidates such as Edwin Jackson because the Diamondbacks' lineup is stacked with dangerous left-handed hitters to whom Thompson largely will be an unknown quantity.
You would expect the Irish to beat Saudi Arabia and, although Cameroon are an unknown quantity, you really wouldn't fancy them to progress beyond the opening stages.