It happened at West Third Street and Sixth Avenue just after 6:15 a.m.
The 45-year-old victim was walking when she saw a man she knew from her past and the two got into a verbal dispute.
She was slashed in the neck and ran to the subway where she reported the incident.
She was taken to Bellevue Hospital where she was said to be stable.
The male suspect fled the scene.
No arrests have been made.
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