Parate (sustantivo, masculino)
 

We locally call parate a recession or any deep or lasting slowing-down of the economy. It's a popular term used mostly by those who are not familiar with economic concepts and "jargon". How do the folks call it in English?

Recession is a pretty common and well known term here even among the uneducated masses, so that is what I would expect most all US English speakings to say, even if they didn't understand how a recession is defined or when it becomes a depression.

In economics technical jargon, there is also "stagnation", when economy has receded and it won't grow for a while.

En México es una recesión o estancamiento. :)

Besides recession, economic turndown is one you may hear in English.

The simplest way of saying this is tough times

This thread reminds me "Groucho y yo" (don't remember the title in English) but it's the autobio by Groucho Marx, and had a good section about the 1929 crisis... The way he explained then, it is still very applicable now... (so if you get the original version of the book, you may get a lot of inspiration...)

The 98 Generation authors would talk about the "marasmo intelectual", but "a complete standstill" may perfectly apply to economic matters...

Thank you everybody for your suggestions.

Also, what about "a slump"? It's pretty similar to parate when applied to the economy, but, is it 'popular/colloquial' enough?

Slump can be used in a similar way, but I don't hear it as often when referring to the economy as a whole. But it still would sound normal to me.