The phrase "a foreign matter" is correct and usable in written English.
It can be used to refer to something that is unfamiliar or not native to a particular context or environment.
Example: "The scientist discovered a foreign matter in the sample that could indicate contamination."
Alternatives: "an external substance" or "a non-native element".
With terror attacks abroad and the influx of hundreds of thousands of refugees, the Syrian crisis is no longer a "foreign" matter for Europe or the United States; it has come to seem a matter of national security.
Patrick H. Caddell, who was President Jimmy Carter's pollster, recalled the internal agonizing in the 1980 campaign -- the last time there was a contest this close this late in the season -- when the dynamic was affected by a foreign matter largely beyond the candidates' control, the Iranian hostage crisis.
It is obvious that when a foreign matter is absorbed by the plant, it acts against this material through defensive mechanism for protection.
He added, "We took out a piece of foreign matter that a colleague identified as white phosphorous".
A pure and foreign matter that finally found its place as the conductor of this unpredicted collision.
Pearls are formed in oysters by the accumulation of nacre, the material lining the oyster shell, around a solid piece of foreign matter that has become lodged inside the shell.
An embolism is an obstruction in a blood vessel due to a blood clot or other foreign matter that gets stuck while traveling through the bloodstream.
Tweezers x 1 (To remove splinters or foreign matter in a wound).
The Logan Act has functioned primarily as rhetorical ammunition for the party that holds the White House during partisan disputes over a foreign policy matter.
The Pakistani government has not fully explained its action, but government lawyers have described it as a "foreign policy matter" and noted that Pakistan has the right to not renew foreign visas.
Before the year was out, Congress overrode President Ronald Reagan's veto of a bill that imposed sanctions, the first time Mr. Reagan had been rebuffed like this on a foreign policy matter.
