Overlabored can be substituted with many synonyms such as overworked, exhausted, fatigued, tired, spent, drained, burnt out, and weary. Each word represents a different level of exhaustion and fatigue, but they share a similar feeling of being worked too hard. Someone who is overworked or exhausted has been pushed beyond their limits, while someone who is tired or spent may have just reached their threshold. Burnt out and weary individuals have been worked to the point where they have lost their motivation and enthusiasm. Ultimately, these synonyms are useful in expressing the degree of exhaustion someone is feeling.