No pain, no gain, no idea what half these terms mean.
The total amount of work performed in a workout, calculated by multiplying sets times reps times weight, turning your gym session into a word problem that would make a math teacher proud. More volume theoretically means more gains, but also more crying.
The maximum amount of oxygen your body can utilize during intense exercise, measured in milliliters per kilogram per minute. Essentially your engine's horsepower rating, but for breathing.
The act of holding your breath and bearing down during heavy lifts to increase intra-abdominal pressure and spinal stability. Basically, constipation but make it athletic.