na-adjective, noun
Describes something that is barely continuing, often with a sense of being about to stop or fade away. Commonly used for breath, voice, life, or other continuous phenomena.
彼の声は絶え絶えで、ほとんど聞こえなかった。
His voice was faint and barely audible.
絶
With faltering breath, he called for help.
か細い describes something physically thin and weak, often a voice or thread, while 絶え絶え emphasizes the intermittent, about-to-stop quality.
途切れ途切れ means 'in fits and starts' or 'broken', focusing on discontinuity, whereas 絶え絶え suggests a weak, fading continuity.
Reduplication of the verb stem 絶え (from 絶える, 'to cease, to die out'), emphasizing a state of barely continuing.