When someone sees a Millennial doing something typically clueless or unthought out, narcissistically expecting others to acquiesce to what they are doing instead of trying to respect that there are other people pursuing their interests as well. For instance walking through an intersection against a traffic light while simultaneously holding a text conversation they are engrossed in. One could call it "#hashtag millennialing" This can include any oblivious actitivies. Yes it is a double hashtag... This is due to the millennial tendancy to hashtag everything WAY too much. Over hashtaging is another example for using "#hashtag millennialing"
Hailey just came down and told us to keep quiet because she has to work in the morning. It's 930pm... That bitch holds a regular Thursday night house party upstairs that goes till 330am... She's #hashtag millennialing.

Ethan put like 57 hashtags on this Instagram post of his breakfast... What does his half eaten omelette have to do with #Manbuns? Seriously... #hashtag millennialing!
by Seafest42 April 8, 2017
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