The phrase "an unknown face" is correct and usable in written English.
It can be used to describe someone whose identity is not recognized or familiar to the speaker.
Example: "As I walked through the crowded room, I noticed an unknown face in the corner, watching me intently."
Alternatives: "a stranger's face" or "an unfamiliar face".
Until now, McGrath has been an unknown face, though hardly an unknown.
Self-proclaimed defenders of the revolution, the colectivos radio each other from the top of neighbourhood buildings whenever an unknown face comes into their area.
I love it when we can have an unknown face in the lead - the audience will accept her as Amy, not see her as a familiar face playing Amy.
Frith, who left the magazine just as it seemed its sales had peaked, is not an unknown face on TV himself, having appeared on celebrity versions of The Weakest Link, flirting with Anne Robinson, and as a regular contributor to The Apprentice: You're Fired, and Strictly Come Dancing: It Takes Two.
Thus, it is understandable, as Verlyn Klinkenborg writes ("A Knowing Smile on an Unknown Face," Editorial Notebook, May 27), that the discovery of a painting that may be of Shakespeare when he was 39 years old makes us want to believe that the portrait is genuine.
The show was full of surprises: an old man who had apparently been dozing for over a century in the parlour; a copy of Darwin's famous book face down on a shelf; an unknown face suddenly staring back at you from a cracked mirror; a basement lake full of goldfish.
But he remains a relatively unknown face on the national scene and a newcomer to the Senate, where he would like a glowing aura of distinction and a career like that of one of his Democratic idols, Senator Ted Kennedy of Massachusetts.
It says that carriers should remain free to set their own prices and policies for onboard musical instruments.So airbound instruments still face an unknown fate.
The composite face task is a persuasive demonstration of the automatic global-level processing of faces: the top and bottom halves of two familiar faces form a seemingly new, unknown face when viewed together.
This initial model will be used to perform a rough alignment on the unknown face.
She began as a relative unknown facing Samantha Stosur, the world's 11th-ranked player and the 2011 United States Open champion.
