noun
the position of being first (as in rank, power, or influence)
Britain once enjoyed supremacy on the seas
Synonyms: ascendancy, ascendant, dominance, domination, dominion, masterdom, preeminence, preponderance, preponderancy, preponderation, prepotence, prepotency, sovereignty
Related Word: authority, control, driver's seat, power, sway; mastership, mastery, principality, superiority; transcendence