Exhaustment is an intense feeling of mental or physical fatigue, typically resulting from prolonged exertion or stress. However, there are several synonyms that can be used interchangeably to convey similar meanings. For instance, one alternative is "weariness", which suggests being tired or fatigued after physical or mental exertion. Another synonym is "fatigue", which refers to extreme tiredness or a state of exhaustion. "Drained" is another word that can be used to describe the feeling of being emotionally or physically depleted. Lastly, "exhaustion" itself can serve as a synonym for "exhaustment". These synonyms can help express the sense of overwhelming tiredness experienced in various situations.