1)A male testical used in the reproduction process. See Penis/Dick/Cock
2)A word made up in the 8th grade Algebra class through Mrs. Dean's innability to hear. First meaning a pen that went shhh. Soon to become known through a different deffinition. (See 1)
shh-The noise you make when your telling somebody to shut up.
pen-A writing object in which ink is used.
Damn you've got a small shpen.
You like my shpen dont you!?