411 REFERENCE · Wiktionary
Judas window
Reference material by Wiktionary contributors. This retains its source identity and is not 411 news reporting.
English
Noun
A window enabling a prison guard to see into a cell without being seen by the prisoner.
en 1989 James P. Sterba; Creighton Peden Freedom, equality, and social change 314 A prisoner may be confined nude in a cell with a Judas window and intruded upon periodically while there.
en 2017 Theodore Dalrymple The Knife Went In Luckily an officer happened to look through the judas-window in the door and rushed in to save the witness
en eponyms