Synonyms for Initiative:

adj.

all (adjective)
first, inaugural, maiden, initiatory.
beginning (adjective)
initiatory.
incipient (adjective)
initiatory.
initial (adjective)
first, inaugural, opening.

n.

ambition, abrogate, criminalize, force, inventiveness, amendment, backdate, come in, bring in, abolish, amend, energy, decriminalize, drive, codify. clarity, judgment, intelligence, intuition, vision, brilliance, wisdom, lead, reason, intellect, action, leadership, common sense. try, process of elimination, remedy, answer, fix, resolution, punch, compromise, heuristics, tired, get-up-and-go, way out, solution, gumption, push, cure, hustle. window of opportunity, chance, scope, choice, the initiative, opportunity, access, break, Possibilities. energy (noun)
activity, force, get-up-and-go.
enterprise (noun)
hustle, gumption.
initiative (noun)
energy, enterprise, inaugural, push, punch, drive, opening, get-up-and-go, ambition, inventiveness, maiden, go ahead, enterprisingness, first step, initiatory, first, leadership, opening move, action.
venture (noun)
campaign, deed, maneuver, undertaking, task, affair, pursuit, feat, adventure, procedure, project, venture, endeavor, exploit, performance, enterprise, production, scheme, activity.

Other synonyms:

leadership, get-up-and-go. punch, drive. shrewdness
gumption.
Other relevant words:
energy, gumption, action, initiatory, punch, inaugural, ambition, first step, enterprisingness, opening, lead, inventiveness, go ahead, leadership, get-up-and-go, opening move, push, force, maiden, drive, hustle, first.

Usage examples for initiative

  1. Use your own judgment and initiative – Analyzing Character by Katherine M. H. Blackford and Arthur Newcomb
  2. Certainly, since I took the initiative – Who Goes There? by Blackwood Ketcham Benson