The antonyms for the word "most vitrified" could include words like "porous," "permeable," or "porous." While vitrification suggests that something has been made hard, dense, and durable, these antonyms suggest the opposite. They imply that a substance is more easily penetrable, less dense, and less durable. Other antonyms could include words such as "soft," "malleable," "pliable," "flexible," "yielding," "friable," or "brittle." All of these terms suggest that a substance is less rigid or less resistant to external forces. In short, if something is "most vitrified," it is likely to have properties that are precisely the opposite of these antonyms.