Belonging to the third string of a team; one who plays behind the first and second strings.(adjective)
A substitute or replacement.(adjective)
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Use "third-string" in a sentence
"Moments after he called the third-string offense and defense onto the field -- which, he stressed, was for three plays only because of time constraints -- Reid walked toward the line of scrimmage and held everything up for a few precious seconds."
"Cal Sport Media/Zuma Press Greg McElroy Another Jets player railed against the team's splintered locker room Wednesday, when Greg McElroy, a third-string rookie quarterback, took the club to task for what he called its selfishness."
""I'll just tell you this, the one thing I know about Jay Cutler is he's tough," said third-string quarterback Caleb Hanie, who led a late comeback bid."