pioneer (n.)
- adventurer
 - airhead
 - alpinist
 - ancestor
 - announcer
 - antecedent
 - astronaut
 - avant-garde
 - beachhead
 - begin
 - bellwether
 - bridgehead
 - buccinator
 - bushwhacker
 - camper
 - climber
 - coin
 - colonial
 - colonist
 - colonizer
 - commuter
 - cosmopolite
 - cruiser
 - engineer
 - excursionist
 - explorer
 - fare
 - forebear
 - forefront
 - forerunner
 - found
 - front
 - front-runner
 - frontiersman
 - fugleman
 - goer
 - groundbreaker
 - guide
 - hajji
 - harbinger
 - head
 - herald
 - homesteader
 - immigrant
 - initial
 - initiate
 - innovator
 - institute
 - journeyer
 - launch
 - lead
 - leader
 - line
 - maiden
 - mariner
 - messenger
 - mountaineer
 - nester
 - original
 - outpost
 - pacemaker
 - palmer
 - passenger
 - passerby
 - pathfinder
 - pilgrim
 - pilot
 - planter
 - point
 - precedent
 - precursor
 - predecessor
 - primary
 - prime
 - railhead
 - rubberneck
 - rubbernecker
 - sailor
 - sapper
 - scout
 - settler
 - sightseer
 - sooner
 - spearhead
 - squatter
 - start
 - straphanger
 - tourer
 - tourist
 - trailblazer
 - transient
 - traveler
 - trekker
 - trend-setter
 - trigger
 - tripper
 - van
 - vanguard
 - viator
 - voyager
 - wayfarer
 
pioneer (v.)
- actuate
 - begin
 - camper
 - coin
 - create
 - develop
 - discover
 - engineer
 - establish
 - fare
 - found
 - front
 - guide
 - harbinger
 - head
 - herald
 - inaugurate
 - initial
 - initiate
 - innovate
 - institute
 - introduce
 - invent
 - launch
 - lead
 - line
 - mountaineer
 - originate
 - pilot
 - point
 - precede
 - prime
 - revolutionize
 - rubberneck
 - scout
 - spearhead
 - start
 - trigger
 - van