1. (Perhaps by analogy to a bouncing check) An electronic mail
message that is undeliverable and returns an error notification (a "bounce message
") to the sender is said to "bounce".
2. To play volleyball. The now-demolished D. C. Power Lab
building used by the Stanford AI Lab in the 1970s had a volleyball court on the front lawn. From 5 PM to 7 PM was the scheduled maintenance time for the computer, so every afternoon at 5 would come over the intercom the cry: "Now hear this: bounce, bounce!", followed by Brian McCune loudly bouncing a volleyball on the floor outside the offices of known volleyballers.
3. To engage in sexual intercourse; probably from the expression "bouncing the mattress", but influenced by Roo's psychosexually loaded "Try bouncing me, Tigger!" from the "Winnie-the-Pooh" books.
4. To casually reboot a system in order to clear up a transient problem. Reported primarily among VMS
5. (VM/CMS programmers) Automatic warm-start of a computer after an error. "I logged on this morning and found it had bounced 7 times during the night"
6. (IBM) To power cycle
a peripheral in order to reset it.