pioneer

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. One who ventures into unknown or unclaimed territory to settle.
2. n. One who opens up new areas of thought, research, or development: a pioneer in aviation.
3. n. A soldier who performs construction and demolition work in the field to facilitate troop movements.
4. n. Ecology An animal or plant species that establishes itself in a previously barren environment.
5. adj. Of, relating to, or characteristic of early settlers: the pioneer spirit.
6. adj. Leading the way; trailblazing: a pioneer treatment for cancer.
7. v. To open up (an area) or prepare (a way): rockets that pioneered outer space.
8. v. To settle (a region).
9. v. To initiate or participate in the development of: surgeons who pioneered organ transplants.
10. v. To act as a pioneer: pioneered in development of the laser.

Century Dictionary and Cyclopedia

1. n. Milit.. one of a party or company of foot-soldiers who march before or with an army, and are furnished with digging- and cutting-implements, to clear the way of obstructions, repair the roads, dig intrenchments, etc.
2. n. One who or that which goes before and opens and leads or prepares the way for others coming after; specifically, a first or early explorer or experimenter in any department of human enterprise.
3. To go before and open (a way); lead or prepare the way to or for.
4. To act as pioneer; clear the way; remove obstructions.

Wiktionary

1. n. One who goes before, as into the wilderness, preparing the way for others to follow
2. n. A person who is first or among the earliest in any field of inquiry, enterprise, or progress
3. n. obsolete, military A soldier detailed or employed to form roads, dig trenches, and make bridges, as an army advances; a sapper.
4. n. A member of any of several European organizations advocating abstinence from alcohol.
5. n. communism A child of 10–16 years in the former Soviet Union, in the second of the three stages in becoming a member of the Communist Party.
6. v. To go before and prepare or open a way for; to act as pioneer.

GNU Webster's 1913

1. n. (Mil.) A soldier detailed or employed to form roads, dig trenches, and make bridges, as an army advances.
2. n. One who goes before, as into the wilderness, preparing the way for others to follow
3. v. To go before, and prepare or open a way for; to act as pioneer.
4. v. to take part in the early development of; to break ground in; to invent or originate.

WordNet 3.0

1. n. someone who helps to open up a new line of research or technology or art
2. v. open up an area or prepare a way
3. n. one the first colonists or settlers in a new territory
4. v. take the lead or initiative in; participate in the development of
5. v. open up and explore a new area