fly on the wall


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fly on the wall

One who is able to observe something closely but invisibly and without interfering in the situation. I would love to be a fly on the wall in John's house when he finds out his wife bought a new car without telling him.
See also: fly, on, wall

fly on the wall

An unseen observer or listener, as in I wish I could be a fly on the wall when she tells him she's pregnant. [Mid-1900s]
See also: fly, on, wall