The Scotland/Northern Ireland idiom for gagging without vomiting.
NOTE: The idiom is *the* dry boak
. It it never *a* dry boak
It is from this idiom that the word boak
escaped to take on a life of its own (along with the alternate spelling boke
) -- with some people using boak
) to mean "the dry boak," and others meaning normal vomiting.
"It would huv gied ye the dry boak tae hear them sookin up tae him, aw sweetie sweetie." (Anne Donovan, Hieroglyphics: And Other Stories, 2001)