WordNet (r) 3.0 (2006):

paramountcy
    n 1: the state of being paramount; the highest rank or authority

Moby Thesaurus II by Grady Ward, 1.0:

82 Moby Thesaurus words for "paramountcy":
   accent, acme, authority, authorization, be-all and end-all,
   blue ribbon, championship, command, concern, concernment,
   consequence, consequentiality, consideration, control,
   directorship, dominion, effectiveness, emphasis, excellence,
   exquisiteness, first place, first prize, headship, hegemony,
   height, high order, high rank, highest, imperium, import,
   importance, influence, interest, jurisdiction, kingship,
   leadership, lordship, magnificence, management, mark,
   marvelousness, mastership, mastery, matchlessness, materiality,
   maximum, merit, moment, most, ne plus ultra, new high, note, palms,
   peerlessness, power, precedence, preeminence, presidency, primacy,
   priority, record, rule, say, self-importance, significance,
   sovereignty, splendidness, splendiferousness, stress, superbness,
   supereminence, superexcellence, superfineness, superiority,
   supremacy, sway, top spot, unsurpassedness, value, weight, worth,
   zenith