A common British slang term, for when a person is feeling extremely horny, sexually aroused.
Generally used to indicate a more heightened state of sexual need, than merely proclaiming being horny.
A sort of sexual excitement, unsatisfied as of yet, though a determined effort to satisfy that quest, is indicated by the use of the term.
Also an older used term, to refer to one's chimney.
Used at the time of Chimney Sweeps, though not common today.