1. (n.) One who goes into the wilderness, preparing the way for others to follow; as, pioneers of civilization; pioneers of reform\.

2. (n.) A soldier detailed or employed to form roads, dig trenches, and make bridges, as an army advances.

3. (v. t. & i.) To go before, and prepare or open a way for; to act as pioneer.

Seabee actuate advance guard adventurer airhead alpinist ancestor announcer antecedent astronaut avant-garde battle line be in front be the front-runner beachhead begin bellwether blaze the trail break ground break the ice break the trail bridgehead buccinator bushwhacker camper climber coin colonial colonist colonizer combat engineer comers and goers commuter cosmopolite create cruiser develop discover earliest engineer establish excursionist explorer fare farthest outpost first line forebear forefront foregoer forerun forerunner forge ahead found front front line front rank front runner front-runner frontiersman fugleman globe-girdler globe-trotter go before goer groundbreaker guide hajji harbinger head head up herald homesteader immigrant inaugurate initial initiate innovate innovator institute introduce introduce new blood invent jet set jet-setter journeyer kick off launch lay the foundation lay the groundwork lead lead off lead runner lead the way leader line maiden make innovations mariner messenger mountaineer neologize nester open up original originate outguard outpost pacemaker palmer passenger passerby pathfinder pilgrim pilot planter point precede precedent precursor predecessor primary prime put in motion railhead revolutionize rubberneck rubbernecker sailor sapper sapper and miner scout set in motion set off set up settler show the way sightseer sooner spearhead squatter stand first stand in front start stormy petrel straphanger take the initiative take the lead take the plunge tourer tourist trailblazer trailbreaker transient traveler trekker trend-setter trigger tripper usher in van vanguard vaunt-courier viator visiting fireman voortrekker voyager voyageur wayfarer world-traveler