Police said the stabbing happened in the Loop in the 100-block of South Wabash Avenue around 1:10 p.m.
A 36-year-old woman was arguing with the driver of a silver sedan, and at one point, the altercation became physical, police said.
Police said that driver took out a sharp object and stabbed the woman before getting back into the sedan and fleeing the scene.
The victim, stabbed in the chest and arm, was transported to Northwestern Hospital in good condition.
There is no one in custody, and Area Three detectives are investigating.
Police did not immediately provide further information about the stabbing.
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