[pi.o.neer] n [MF pionier, fr. OF peonier foot soldier, fr. peon foot soldier, fr. ML pedon-, pedo--more at pawn] (1523) 1: a member of a military unit usu. of construction engineers
2. a: a person or group that originates or helps open up a new line of thought or activity or a new method or technical development b: one of the first to settle in a territory
3: a plant or animal capable of establishing itself in a bare, barren, or open area and initiating an ecological cycle
[2]pioneer vi (1780): to act as a pioneer "~ed in the development of airplanes" ~ vt 1: to open or prepare for others to follow; also: settle
2: to originate or take part in the development of [3]pioneer adj (1840) 1: original, earliest
2: relating to or being a pioneer; esp: of, relating to, or characteristic of early settlers or their time