"Four Wheel Alignment" .....
I'm not going to try and second guess if all alignment shops would be confused if someone asked for a four wheel alignment. But, if they have a clue, they should know what you are asking for. When I first bought my Jeep, I took it to a shop (Goodyear Tire) in town for a front end alignment. They did a four wheel alignment check on it ... in other words, they checked to make sure the front and rear axles were running parallel to each other (I asked the Tech doing the work, BTW).
I do my own alignments at home. I check to make sure my axles are (still) running parallel to each other. I then check to make sure the front axle is (still) centered under the front end. I do this with the vehicle at static, IOW's the vehicle sitting with weight on the suspension. I do this to see if there may be a problem in the rear suspension, or if my (adjustable) LCA's have come out of adjustment or have been bent, or if the (adjustable) track bar is out of adjustment or has been bent. Then I check the other aspects of the alignment.
Because a lot of us on this board have and "abuse" custom suspension components, it is important (if you drive on the street) to check the condition and geometry of all the suspension components. JMO ...
Les