Trou.
ETYM Old Eng. shaft, schaft, as. sceaft.
1. A line that forms the length of an arrow pointer.
2. A long rod or pole (especially the handle of an implement or the body of a weapon like a spear or arrow).
3. A vertical passage into a mine.
4. A vertical passageway through a building (as for an elevator).
5. The vertical part of a column.
ETYM Old Eng. welle, AS. wella, wylla, from weallan to well up, surge, boil; akin to Dutch wel a spring or fountain. Related to Well.
1. A deep hole or shaft dug or drilled to obtain water or oil or gas or brine.
2. An abundant source; SYN. wellspring, fountainhead.
3. An open shaft through the floors of a building (as for a stairway).
4. An enclosed compartment in a ship or plane for holding something as e.g. fish or a plane's landing gear or for protecting something as e.g. a ship's pumps.