When a feeling of embarrassment or
shame is experienced that is so powerful that it is analogous to an
orgasm; shame is to a shamegasm as pleasure is to an
orgasm.
When Hannelore, shy and suffering from OCD, was informed that she had been "flashing a lot of underpants
action" while playing drums, she had a
major shamegasm and was shocked silent for several minutes.
("Shamegasm" was first coined by Jeph Jacques, author of the webcomic Questionable
Content)