OK!! So you just landed to GYM and you are quite astonished with the kind of lingo being used there. The terms seem to be so fascinating but nobody has time to explain it to you. So here are some of them compiled from different sources:

1. Abs, abdominals
The muscle in the front of the stomach that form the six-pack when one’s body fat is fairly low. Their function is to draw the base of the ribcage and the hips towards each other, as occurs when performing crunches. Abs can certainly not be attained by doing zillions of crunches in a day, it requires a fool-proof diet plan as well.

2. Aerobic
Aerobic means "with oxygen" or “requiring oxygen”, and refers to the use of oxygen in a muscle's energy-generating process. When describing exercise, it refers to extended sustained levels of exertion during which metabolic processes that provide energy are dominated by the complete oxidation of nutrients. A method of conditioning the cardio-respiratory system by performing an activity that uses large muscle groups, is rhythmic, elevates the heart rate for a period of time, and increases the intake of oxygen.
Thus, aerobic exercise pertains to the level where we exhaust our body to increase our metabolism process and increase the requirement of oxygen. Hope it explains why you need to breathe properly while running on treadmill.

3. Anaerobic Exercise
Short-term, high-intensity exercise (i.e., sprinting, weight lifting) that uses carbohydrates for energy.
It includes lower intensity activities performed for longer periods of time. Activities like walking, running, swimming, and cycling require a great deal of oxygen to generate the energy needed for prolonged exercise. It is typically used by athletes in non-endurance sports to build power and by body builders to build muscle mass
4. Anaerobic Threshold
The anaerobic threshold (AT) is the exercise intensity at which lactate starts to accumulate in the blood stream. This happens when it is produced faster than it can be removed (metabolized). This point is sometimes referred to as the lactate threshold, or the onset of blood lactate accumulation (OBLA). When exercising below the AT intensity any lactate produced by the muscles is removed by the body without it building up.

The anaerobic threshold is a useful measure for deciding exercise intensity for training and racing in endurance sports (e.g. distance running, cycling, rowing, swimming and cross country skiing), and can be increased greatly with training.

3. Amino acids
Basic building blocks of protein. No prizes for guessing that it is certainly required for building up muscles.

4. Bodyfat percentage
The amount of fat in your body, generally expressed as a percentage.

5. Compound Exercise
An exercise that targets a muscle group simultaneously; usually the movement involves flexing or extending at least two joints. Lat pulldowns, squats, and bench press are all compound movements. Exercises like leg curls, leg extensions, and flyes are not compound movements.

6. Electrolytes
Minerals such as sodium, potassium, magnesium, and calcium used by cells in the creation and elimination of membrane potentials used to propagate nerve impulses and muscular contraction.

7. Failure
Lifting a weight until your muscles are so fatigued they cannot perform another repetition.

8. Forced rep
A repetition performed with assistance from a spotter after a lifter has reached the point of failure with a given weight.

11. One rep maximum
The greatest amount of weight that can be handled by a lifter for a single repetition in good form.

12. Overtraining
Training beyond the body’s ability to repair itself. This can be caused by training the same body parts too frequently so that the body does not have time to recover before the next workout; workouts that are consistently harder than the body is able to recover from fully; or impairment of the body’s normal recovery ability due to nutritional deficiencies, illness, or stress.
Besides impairing athletic performance, overtraining can increase the risk of injury or disease. Symptoms of overtraining include fatigue, reduced performance.

13. Absolute Strength
The maximum amount a person can lift in one repetition.

14. Basal Metabolic Rate (BMR)
The energy requirements necessary for maintenance of life processes such as heart beat, breathing and cell metabolic activities.

15. Burn - As in "going for the burn"
In endurance exercise, working muscles until lactic acid build-up causes burning sensation.

16. Cheating
Too much weight used on an exercise, therefore relying on surrounding muscle groups for assistance in the movement; or changing joint angles for more leverage, as in arching back in bench press.

17. Cool-Down
Rhythmic, low-intensity aerobic activities that provide a transition period between high-intensity aerobic work and less aerobically taxing calisthenics, stretching or the end of the workout.

18. Negative Reps
One or two partners help you lift a weight up to 50% heavier than you would normally lift to finish point of movement. Then you slowly lower weight on your own.

19. Power Training
System of weight training using low repetitions, heavy weights.

20. Progressive Resistance
Method of training where weight is increased as muscles gain strength and endurance. The backbone of all weight training.

21. Proper Form
Focus on the proper motion of the exercise and concentrate on the specific muscles being used. Do not sacrifice proper form to lift heavier weight or to perform more repetitions. Proper form also means lifting in a smooth, fluid motion. If you feel strain elsewhere, you should re-evaluate the amount of weight you are lifting or have a qualified professional critique your exercise motion.

22. Proper Posture
Maintaining proper posture will greatly reduce chances of injury and maximize exercise benefit. When standing always keep your feet shoulder-width apart. Do not lock your knees. Locking your knees can put unnecessary strain on them. Keep your back flat and straight, making sure not to twist or arch it in order to complete a repetition.

23. Proper Technique
To get the most out of strength training and to reduce the chance of injury, use proper weight training techniques. These include working your muscles through their full range of motion (but not locking any joints), lifting at a speed at which you can control the weight and stop easily if necessary.

24. Repetition
One complete movement of an exercise.

25. Repitition Maximum (RM)
This is the maximum number of repetitions per set that can be performed at a given resistance with proper lifting technique. Thus, a set at a certain RM implies the set is performed to momentary voluntary fatigue. 1RM is the heaviest resistance that can be used for one compete repetition of an exercise. 10 RM is a lighter resistance that allows completion of 10 (but not 11) repetitions with proper exercise technique.

26. Strain
Muscle pull; a stretch, tear or rip of the muscle or adjacent connective tissue, such as fascia or muscle tendon. Usually occurs from an excessive effort.

27. Strength
Amount of force a muscle or muscle group can exert against resistance.

28. Strength Training
Working the muscles against external resistance to increase muscular strength, muscular endurance or muscular power.

29. Super Set
Alternating back and forth between two exercises until the prescribed number of sets is completed.

30. Warm-Up
A balanced combination of increasingly intense aerobic exercises and stretches that prepare the body and the mind for more vigorous exercise.