PR: personal record. Usually the 1RM for an exercise.
Rippetoe, Mark: Well respected strength training coach and renowned author from USA. Wrote Starting Strength. If there’s only one book about training that you should read, it’s this one!
Rep: Repetition. A single cycle of lifting and lowering (or lowering and lifting) a weight.
RM: Repetion Maximum. Maximum amount of weight one can lift in a given number of repetitions for a given exercise. Ex 6RM When no number is present, it usually refers to the 1Rep-Max
ROM: Rang of motion
Testosterone: androgen steroid hormone. It is the principal male sex hormone. It plays a key in the development of male reproductive organs and is responsible for secondary sexual characteristics such as increased muscle and bone mass, lower voice tone and body hair growth. In men and woman it also stimulates sex drive. Synthetic testosterone is used as an anabolic drug, usually referred to as steroids, roids or juice.