pit 1 
(pĭt)
(pĭt)n.
1. A natural or artificial hole or cavity in the ground.
2.
a. An excavation for the removal of mineral deposits; a mine.
b. The shaft of a mine.
3. A concealed hole in the ground used as a trap; a pitfall.
4. A small indentation in a surface: pits in a windshield.
5.
a. A natural hollow or depression in the body or an organ.
b. A small indented scar left in the skin by smallpox or other eruptive disease; a pockmark.
c. Zoology Either of a pair of depressions between the nostril and the eye of a pit viper that contain heat-sensing organs.
d. Botany A cavity in the wall of a plant cell where there is no secondary wall, as in fibers, tracheids, and vessel elements.
e. Informal An armpit.
6. An enclosed, usually sunken area in which animals, such as dogs or gamecocks, are placed for fighting.
7.
a. The section directly in front of and below the stage of a theater, in which the musicians sit.
b. Chiefly British The ground floor of a theater behind the stalls.
8.
a. The section of an exchange where trading in a specific commodity is carried on.
b. The gambling area of a casino.
9.
a. A sunken area in a garage floor from which mechanics may work on cars.
b. often pits Sports An area beside an auto racecourse where cars may be refueled or serviced during a race: pulled into the pits to have the tires rotated.
10.
a. Hell. Used with the.
b. A miserable or depressing place or situation.
c. pits Slang The worst. Used with the: "New York politics are the pits" (Washington Star).
11. Football The middle areas of the defensive and offensive lines.
v. pit·ted, pit·ting, pits
v.tr.
1. To mark with cavities, depressions, or scars: a surface pitted with craters.
2. To set in direct opposition or competition: a war that pitted brother against brother.
3. To place, bury, or store in a pit.
v.intr.
1. To become marked with pits.
2. To retain an impression after being indented. Used of the skin.
3. To stop at a refueling area during an auto race.
[Middle English, from Old English pytt, ultimately from Latin puteus, well; see pau-2 in the Appendix of Indo-European roots.]