See opening in Webster's New World Roget's A-Z Thesaurus II
noun
An open space allowing passage:
aperture, hole, mouth, orifice, outlet, vent. See openThe initial stage of a developmental process:
beginning, birth, commencement, dawn, genesis, inception, nascence, nascency, onset, origin, outset, spring, start. See startThe act or process of bringing or being brought into existence:
beginning, commencement, inauguration, inception, incipience, incipiency, initiation, launch, leadoff, origination, start. (Informal) kickoff. See startA favorable or advantageous combination of circumstances:
break, chance, occasion, opportunity. (Informal) shot. See luck
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