It literally means “at the order” but translates to something more like “at your service”, it’s what servers in restaurants or people selling things on the street say to let you know they’re ready to receive your order.
I suspect this isn’t exclusive to Colombia but I don’t recall hearing it in Spain and it is very common here – I’m trying to give you guys colloquial Spanish that’s common here, that will prove useful to you if you visit, and that you probably wouldn’t have learned otherwise (textbooks, courses, Duolingo, etc.).
When I was in Cartagena I heard this all the time. There would be employees for every restaurant, bar, and cafe standing out in front of them with menus trying to entice people to come in, and they would frequently use this phrase to indicate they were open for business. The street vendors selling everything from straw hats to cigarettes and candy to beer would use this phrase with the same intention.
In Bogota and Medellin, thankfully, the vendors are nowhere near as aggressive (one of the reasons I didn’t like Cartagena, it’s very touristy), so this phrase is only heard once you’ve indicated you want to engage in some sort of business with someone, e.g. you’ve just sat down at a restaurant and a waiter hands you a menu and says “a la orden”, indicating that they’ll take your order whenever you’re ready (you will likely have to flag them down when you are ready, they don’t check on you occasionally like servers in the states do).
I learned to speak conversational Spanish in six months using TV shows, movies, and even comics: I then wrote a book on how you can, too
I have a whole method and a book I wrote about it called The Telenovela Method where I teach you how to learn Spanish from popular media like TV shows, movies, music, books, etc. that you can all find online for free. It was the #1 new release in the Spanish Language Instruction section on Amazon for nearly a month after it came out and currently has 17 reviews there with a 4.9/5 stars average. It's available for $7.99-$9.99 for the e-book version depending on who you buy it from (Kindle version on Amazon is now $7.99) and $16.99 for the paperback (occasionally a bit cheaper, again, depending on who you buy it from).
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