peeping Tom
noun
A person who derives sexual pleasure from secretly watching people undressing or engaging in sexual activity.And I think I've got a pretty good idea of who our peeping Tom was....
- He consents to being an admiring observer but not a peeping Tom.
- A peeping Tom used hidden cameras to videotape women in their house in Galway city.
Origin
From the name of the person said to have watched Lady Godiva, Lady ride naked through Coventry.