Supremacy is the state of being on top — holding more power, skill, or control than anyone else in some field. "Naval supremacy", "economic supremacy", "the struggle for supremacy in the party." It is stronger than *dominance* and stronger still than *advantage*: supremacy suggests nobody else is even in the running. The word is uncountable and usually appears with *over* ("supremacy over its rivals") or after words like *air*, *military*, *technological*. Two things worth noticing. First, when it attaches to a group of people rather than to a skill — *white supremacy*, *male supremacy* — it stops being neutral and names a racist or sexist belief system; context does all the work there. Second, in ordinary sports and business talk it is a favourite of headline writers precisely because it is grand: "Taiwan's supremacy in chipmaking" says more than "Taiwan is good at chips." Stress the second syllable: su-PREM-acy.