The body style we in the US call a "station wagon" seems to have more variants on what to call it than almost any other body style, with manufacturers often using their own idiosyncratic names, much more so than they do for, say, a coupé or a sedan/saloon. But why?
In addition to station wagon, I bet pretty much everybody reading this can rattle off a few others: estate car, break/brake, shooting break (for two-door variants), wagon, carryall, suburban, variant (a VW favorite), weekender (Citröen liked that one), and variants like sportwagon, kammback, and squareback. That's a lot of euphemisms for one of the most practical body styles around.
It seems that the very first vehicles we'd recognize as being station wagons were largely custom wooden-bodied variants of Model Ts, and were known as "depot hacks" because they were used to carry folks and their luggage to and from train depots. "Hack" referred to the archaic term "hackney", a horse-drawn taxi (and the "Hackney" name traces its way back eventually to the Spanish word jaca, which Uncle Internet tells me is some kind of little horse). Depot Hacks started off as horse-drawn affairs, and the name just got applied to their motorized replacements. "Station Wagon" was just another name for these depot hacks, so the "station" in station wagon is referring specifically to train stations. The first actual production wagon (as in, not custom) was the 1923 Star. It's as pleasingly cottage-looking as you're probably picturing, too.
Okay, so, station wagon=big useful car to take you and your crap to the train station. Swap "train station" for "airport" and you pretty much have a big part of what we use station wagons for today. So what about those other terms? "Estate car" is pretty straightforward– estates are big places for rich people full of the sorts of activities that require bulky equipment: saddles, polo mallets, the unconscious body of your mouthy valet– so it makes sense a big, wagon-like car would be associated with them.
Shooting brake has a more interesting etymology. In my head, since shooting brakes tend to be fast, 2-door sportscar/wagon hybrids, I assumed "shooting" was a reference to speed. It's not. It's more a reference to things like formal, ritual fox slaughter, as "shooting" refers to a car to carry shooting parties. As in groups of upper class folks with rifles, out for a jaunty day of killing things. The "break" or "brake" part comes from a particular sort of carriage chassis used to "break" willful horses. The French use of "break" for a station wagon is basically the same, coming from the French term break de chasse, or "hunting break."
So, to recap, we call our wagon-type cars what we call them thanks to trains, guns, and wild horses. Pretty cowboy/badass for the old archetypal mom-mobile.