hash collision n.
[from the techspeak] (var. `hash clash') When used of people,
signifies a confusion in associative memory or imagination,
especially a persistent one (see thinko). True story: One of us [ESR] was once
on the phone with a friend about to move out to Berkeley. When
asked what he expected Berkeley to be like, the friend replied:
"Well, I have this mental picture of naked women throwing Molotov
cocktails, but I think that's just a collision in my hash
tables." Compare hash
bucket.