Up heaved typically means to lift or thrust something forcefully upward. The opposite of up heaved would be to lower or bring something downward. Therefore, some antonyms for up heaved could include lowered, lowered down, placed down, set down, dropped, or lowered gently. These words indicate a gradual or controlled descent, as opposed to the abrupt upward motion implied by up heaved. Similarly, antonyms for up heaved could include words such as settled or stabilized, meaning that an object remains in a stable position rather than being lifted or thrust. Ultimately, antonyms for up heaved depend on the specific context and intended meaning of the word in question.