look up any word, like plopping:
 
1.
Placing and moving the head of your penis up and down between a females labia majora to lubricate and stimulate for preparation of penile insertion.
He started clam shucking his wife while she slept in hopes of having sex.
by Seafood Chef July 30, 2008
 
2.
the act of orally pleasing a woman while she sits on the toilet, usually while she is in the act of pooping.
I gave my girlfriend the ill clamshucking while she took a dump.
by clamshucker23 April 12, 2011