What is Stalagmite?
1.
The act of ruining a joke, or being not funny. (To replace the awkward silence after someone kills a joke).
After Pat tried to add on to a joke with a dumb comment, instead leaving an awkward silence we said to him "Stalagmite". (Which indicates all are in consensus that he is done talking and should stop before he looks even more dumb)
See
2.
The act of being not funny
"After Pat made a dumb joke, we all told him that he was stalagmite"
3.
A protrusion that can be used in a number of ways. It is stiff, unchanging, and can endure excessive amounts of pressure. It can vary in length and girth, and it usually is very straight and points in an upwardly direction.
"She rode my stalagmite all night long. I didn't even have to move."