1. Home
2. Idioms
3. fly on the wall

fly on the wall

---

---

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