MAYBE it was because they had met on OkCupid. But when the dark-eyed musician with artfully disheveled hair asked Shani Silver, a social media and blog manager in Philadelphia, out on a “date” Friday night, she was expecting at least a drink, one on one.

“At 10 p.m., I hadn’t heard from him,” said Ms. Silver, 30, who wore her favorite skinny black jeans. Finally, at 10:30, he sent a text message. “Hey, I’m at Pub & Kitchen, want to meet up for a drink or whatever?” he wrote, before adding, “I’m here with a bunch of friends from college.”

Turned off, she fired back a text message, politely declining. But in retrospect, she might have adjusted her expectations. “The word ‘date’ should almost be stricken from the dictionary,” Ms. Silver said. “Dating culture has evolved to a cycle of text messages, each one requiring the code-breaking skills of a cold war spy to interpret.”

“It’s one step below a date, and one step above a high-five,” she added. Dinner at a romantic new bistro? Forget it. Women in their 20s these days are lucky to get a last-minute text to tag along. Raised in the age of so-called “hookup culture,” millennials — who are reaching an age where they are starting to think about settling down — are subverting the rules of courtship.