hegemonism n.

1560s, "preponderance, dominance, leadership," originally of predominance of one city state or another in Greek history; from Greek hēgemonia "leadership, a leading the way, a going first;" also "the authority or sovereignty of one city-state over a number of others," as Athens in Attica, Thebes in Boeotia; from hēgemon "leader, an authority, commander, sovereign," from hēgeisthai "to lead," perhaps originally "to track down," from PIE *sag-eyo-, from root *sag- "to seek out, track down, trace" (see seek). In reference to modern situations from 1850, at first of Prussia in relation to other German states.

word-forming element making nouns implying a practice, system, doctrine, etc., from French -isme or directly from Latin -isma, -ismus (source also of Italian, Spanish -ismo, Dutch, German -ismus), from Greek -ismos, noun ending signifying the practice or teaching of a thing, from the stem of verbs in -izein, a verb-forming element denoting the doing of the noun or adjective to which it is attached. For distinction of use, see -ity. The related Greek suffix -isma(t)- affects some forms.