to change something completely, especially into something different and better彻底改变(尤指变成更好的他物)
A few centuries ago alchemists thought they could transmute lead into gold.几个世纪以前炼金术士以为他们能把铅变成金子。
Plutonium transmutes into/to uranium when it is processed in a nuclear reactor.钚在核反应堆中经过处理就变成了铀。