sześćdziesiątka

Etymology
From. The slang meaning comes from the Article 60 of the Polish Penal Code which means "extraordinary mitigation of punishment". Usually means that someone has cooperated with the police. Originally prison slang, nowadays used in general slang.

Noun

 * 1) sixty
 * 2) sixty
 * 3)  something assigned the number sixty: bus line, road, candidate on a ballot, etc.
 * 4)  sixty-year-old woman
 * 5)  informer, stool pigeon, snitch