Here's peon from Dictionary.com:
Pioneer:pe·on1 [pee-uhn, pee-on]
–noun
1. (in Spanish America) a farm worker or unskilled laborer; day laborer.
2. (formerly, esp. in Mexico) a person held in servitude to work off debts or other obligations.
3. any person of low social status, esp. one who does work regarded as menial or unskilled; drudge.
[Origin: 1820–30; < Sp peón peasant, day laborer < VL *pedōn- (s. of *pedō) walker (whence ML pedōnés infantry, OF peon pawn2), deriv. of L ped- (s. of pés) foot]
pi·o·neer [pahy-uh-neer]
–noun
1. a person who is among those who first enter or settle a region, thus opening it for occupation and development by others.
2. one who is first or among the earliest in any field of inquiry, enterprise, or progress: pioneers in cancer research.
3. one of a group of foot soldiers detailed to make roads, dig intrenchments, etc., in advance of the main body.
4. Ecology. an organism that successfully establishes itself in a barren area, thus starting an ecological cycle of life.
5. (initial capital letter) Aerospace. one of a series of U.S. space probes that explored the solar system and transmitted scientific information to earth.
6. (initial capital letter) (formerly) a member of a Communist organization in the Soviet Union for children ranging in age from 10 to 16. Compare Komsomol, Octobrist.
–verb (used without object)
7. to act as a pioneer.
–verb (used with object)
8. to be the first to open or prepare (a way, settlement, etc.).
9. to take part in the beginnings of; initiate: to pioneer an aid program.
10. to lead the way for (a group); guide.
–adjective
11. being the earliest, original, first of a particular kind, etc.: a pioneer method of adult education.
12. of, pertaining to, or characteristic of pioneers: pioneer justice.
13. being a pioneer: a pioneer fur trader.
[Origin: 1515–25; < MF pionier, OF peonier foot soldier. See peon, -eer]