: someone who is able to secretly watch or listen to other people
What might the proverbial fly on the wall have heard if four leading scientists had met over dinner in 1949 …—Publishers Weekly
ˈflī-ȯn-ṯẖə-ˈwȯl
-än-
: having or involving an inconspicuous but effective point of observation
… fly-on-the-wall observations of aspects of daily life …—Will Manley
Cite this Entry
“Fly on the wall.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fly%20on%20the%20wall. Accessed 8 Jul. 2026.
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