The antonyms for the word 'most decomposed' would be 'least decomposed,' 'fresh,' 'recent,' 'unspoiled,' 'unaffected,' 'untouched,' 'preserved,' 'sound,' and 'healthy.' These words mean that the object or material is in its original form and has not undergone any significant change or alteration. Some other antonyms that are relevant to this context would be 'intact,' 'unaltered,' 'unbroken,' and 'sound.' These antonyms can be used in different situations like food, organic matter, or even in the context of musical instruments. Using these antonyms can help to create a better understanding of the current state of objects and can lead to a better evaluation of their quality.