Here is a training term you won't hear so often around the local gym. You're more likely to encounter it online or when talking to a trainer.
Training Economy: The efficiency at which you train all of the traits that you want, without taking more time, energy, or workouts than is necessary.
Put another way, it's using the most efficient exercises to get the job done.
In other words, if you want to train your grip (hands, forearms), your biceps, and your back, you can do three different exercises - say a plate pinch, some biceps curls, and some rows. Or, you can do thick-handled chinups and get all three at once.
Or another example - you could do your exercises, then your stretches for the areas of your body you don't intend to stretch. Say, squats and chest, arm, and back stretches. Or you could put your stretches in between sets of your squats and let your muscles strength while your body replenishes the reserves in your leg muscles for the next set.
Still another - you could do supersets in order to cut down on overall time of the workout.
Using training economy is about getting the most results with the least waste - critical for folks with more workout to do than they have time to do.
Also see this excellent article from 12 years back from Joe DeFranco on this exact subject.