świadek

1. witness (One who sees or has personal knowledge of something and may report on it)
2. witness (someone called to give evidence in a court)
3. witness (someone who can witness the signing of a document)
4. (obsolete) residual detached elevation of land, part of an originally uniform upland
5. (obsolete) witness (something that serves as evidence; a sign or token)
6. (obsolete) mound left intact when collecting soil in excavations, planting, deepening ponds, etc., in order to measure the volume of the selected soil