Britannica Dictionary definition of BEST superlative sort of 1good or of 2well 1  a  : much better than all Other individuals in high-quality or worth It is best to don your best /ˈæs.tə.rɔɪd/ Anyone of many small planets that go across the Sunshine, that's not thought of a true planet or even a comet ● احفظ الفيديوهات