to meet up
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to get together
1 The verb to meet up is the preferred form when going out to see friends or anyone at an appointed place and time — usually a social outing like a movie, nightclub, café, beach, etc.
The thing is that meet on its own is kind of official and formal in most cases. Plus, meet on it's own can also refer to meeting or being introduced to someone for the first time, like I'd like you to meet my sister. So instead of saying, for instance, I met my friends last night, you'll most often hear Americans say I met up with my friends last night. It just sounds more sociable.
Nina arrives in New York City and calls her former roommate to see if they can possibly see each other while she's in town.
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Nina: Diana, hey, it's me, Nina. How are you doing? Are you going to be in the city this weekend?
Diana: Hey! Yeah!
Nina: Want to meet up?
Diana: You know it! There's a cute café down the street from my place. I'll text you the address. Can't wait!
2 In the context of connecting with people in person, you'll also hear the phrasal verb get together. For the most part, it means the same thing as meet up, except that we normally expect more than two people to get together — it's more like a party.
In fact, the noun get-together [stress the word get] is more or less synonymous with PARTY, although get-togethers are usually less "formal" — usually no more than a dozen or so friends grilling, watching a game, a movie, hanging out in the pool, etc. A party, on the other hand, usually marks an occasion like a birthday or anniversary, a promotion, an engagement, etc. and involves invitations, decorations, fancy food, perhaps catering and a DJ, dancing, etc. Get-togethers are much more informal and intimate, no special occasion required — just friends, well... getting together.
This meme is making fun of the kinds of people who gather at meetups: in this case, computer geeks, sitting around coding and giggling. To chuckle means to laugh quietly or even to yourself.
Note that unlike get-together, the noun meetup (stress the word meet) doesn't quite convey the same meaning as its corresponding phrasal verb; the verb meet up implies getting together with someone socially, to chat, eat, hang out, etc. However, a meetup is actually kind of a new thing; an organized event, where people with a similar hobby or interests gather at a venue to have seminars, workshops, lectures, etc. They organize these meetups through an app/website called Meetup.
However, you may sometimes hear it in the traditional sense of meeting up with friends: At our last meetup, Gary got drunk and made a spectacle of himself, so he's not coming to our next one.
More Examples:
Hey, do you want to meet up for lunch later?
—Sure, where do you want to go?
Heeey! Long time no see! Let's meet up soon — we've got some catching up to do!
—I mean! How about we meet up at the café by the bookstore this Saturday?
Hey, are you going to Evan's party tonight?
—Yep.
What do you say we meet up beforehand and go together?
—Sounds like a plan. See you then!
Hey, my brother's in town this weekend and we're having a little get-together on Sunday. We're just going to grill out and hang. Join us if you can.
— Nice. Can I bring anything?
Just yourself... and your bathing suit if you want to go swimming.
— Count on it!
