The InnuendoGland was first pin-pointed by ProffessorPlumpkin of MIT in 1963. This monumental achievement was met with somewhat underwhelming interest by the press. An exert from a journal news article at the time:
The gland filters all incoming and outgoing audible and visual symbolism for multiple meanings. In some this gland can be considerablly more efficient than the average.
ProffessorPlumpkin's work was continued by several leading men and women both on and off the stage. The contribution of one GregorWackemoff? should be mentioned here. He came up with the scientific definition of entendres:
Non-entendre(n=0): No meaning, but sound dodgy, such as "my, I wouldn't mind giving her bathroom a good sweeping"
Single-entendre(n=1): One meaning that's dodgy and no other meaning: "I asked the barman for a shag so he gave me one"
Double-entendre(n=2): Standard double meaning, one of which is dodgy i.e. "it was romantic; we were naked under the stars. As she stood up, I stared up into the firmament."
TripleEntendre (n=3): Three meanings, one meaning of which must be dodgy. k-entendre(k): k meanings, one of which must be dodgy.
k+1-entendre(k-1): Same as k-entendre with one extra meaning that is either dodgy or not.
There has been some argument as to whether n-entendres should n-1 dodgy meanings. This is an area of continuing research.