uckumpucky 

any substance that is put on an object to seal off a hole,crack,seam,etc or hold an object together

The gasket was leaking so I put some uckumpucky on it

uckumpucky by Ethanshack November 29, 2004

Duckumpucky 

Refers to a sticky substance that is commonly used to fill or close seams or crevices.

A window or door caulking.

Silicone.

The carpenter used duckumpucky to fill in the cracks after installing the new window.

Duckumpucky by ChuckWhitson December 28, 2008