The term LEG DAY UNIT is composed of three words: 'LEG, ' 'DAY, ' and 'UNIT.' The first word, 'LEG, ' refers to the lower limbs of the body. The second word, 'DAY, ' indicates a period of time, usually 24 hours. The third word, 'UNIT, ' is a measure of something, such as a quantity or a length. The crossword solution for this term is REP, which stands for repetition. Repetition is the act of repeating something multiple times, such as an exercise or a task. Therefore, LEG DAY UNIT can be interpreted as a UNIT of time dedicated to repeating exercises that target the lower limbs of the body.