HESI American Career College Practice Exam

Fatigue describes extreme tiredness or exhaustion, a state of worn-out energy from physical or mental activity. It captures that persistent lack of energy beyond ordinary tiredness, making it the best fit for this question. The other terms point to different ideas: fatal means deadly, feasible means possible or doable, and hydration relates to fluid balance in the body. In everyday and health contexts, fatigue is the standard term used to describe feeling extremely tired or drained.