Washington (CNN) Alexandria Ocasio-Cortez, the new Democratic representative-elect from New York, seized on a social media smear to show she's not afraid to call out sexism or define herself on her own terms.

The incoming lawmaker responded Thursday evening after a journalist referred to her as "a girl" in a tweet critical of her clothing with the message "Dark hates light - that's why you tune it out."

Her words came in response to a now-deleted tweet from Eddie Scarry, a media reporter for The Washington Examiner , in which he posted a photo of Ocasio-Cortez walking down a hallway alongside a caption that read, "Hill staffer sent me this pic of Ocasio-Cortez they took just now. I'll tell you something: that jacket and coat don't look like a girl who struggles."

The tweet was quickly and widely criticized on Twitter, including by other journalists as sexist and inappropriate. It comes after Ocasio-Cortez suggested in a recent interview with The New York Times that it would be challenging to afford an apartment in Washington, before her congressional salary kicks in.

Ocasio-Cortez, a 29-year-old and member of the Democratic Socialists of America, made headlines and sent shockwaves through Washington over the summer when she defeated veteran Democratic Rep. Joe Crowley in a primary challenge. While she hasn't officially started her term as a US representative from New York, Ocasio-Cortez has already become a focal point of attention on Capitol Hill -- and a target of criticism.

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