Eavesdropping – the very word in English suggests a rude and invasive action. It conjures up images of a wiretap, or an ear against the door. To listen in on conversations of people unknown to you may be frowned upon by society at large, but I highly recommend it when learning Spanish (or any new language). If you are serious about not only learning the language, but also the slang, and the common phrases, you should always be listening in on the conversations around you.
My personal philosophy is to bombard yourself with the language, listen only to online broadcasts in the language you aspire to learn, watch soap operas, listen to the newscasts, and yes, listen in on random conversations in public. All will assist you in becoming fluent and knowledgeable in your new tongue.
Spanish has no concise word for eavesdropping. The most common definition is ‘escuchas clandestinas’ or ‘escuchando a escondinas’. To secretly listen. That will do. It is not really eavesdropping if the people conversing nearby are not aware that you are hanging on their every word. And of course there is always that person– in a restaurant, or bank, on the bus or waiting in line for something to open– who speaks so loudly that every word is loud and clear. No need to eschucha clandestina with these human foghorns.
Most conversations are mundane. Someone saying what time they will be home or what they are doing, or what they are eating or planning to eat. No matter. The key is to understand what they have said. Most conversations overheard in any language will likely be dull.
Here, if the talker is in a good mood, you may hear the expression “Que rico” repeated frequently. I was once on a bus, and as we passed a waterfall, the following exchange was heard from two guys sitting behind me: “Que rico la catarata.” “Si, que rico. Agua pura y limpia.” “Si, que rico.” But even a conversation as basic as this one will increase your confidence in learning your new language when you realize that you understood every word.
I have mentioned this before, but it bears repeating: When I first arrived here, I heard over and over the expression “Gracias a Dios”, as “Gracias adios”. I thought I was hearing Thank you, goodbye, when it was actually Thanks to God. It was through hearing the phrase used multiple times in response to something positive that I finally figured it out. If I had not been secretly listening in on those public convos, who knows how long it might have taken me to figure it out.
Eavesdropping also confirmed to me that I was indeed fluent in Spanish. One day years ago, I was walking through town about an hour after a well known local had been gunned down inside a bar in a brazen daytime attack. In the couple of blocks I walked, I passed various groups of people, all discussing the breaking news. By the time I got to where I was going, I knew what had happened, where it had happened, who was the victim, and the possible motive. All through catching bits and pieces of dialogue as I walked.
So if you are learning the language and want an easy and effortless way to increase your fluency bit by bit, do yourself a favor when out in public, and take out the earbuds (unless you are listening to a language lesson), put down the phone, and listen.