Buttress Thread : (n.) Well Completions. A thread profile used on?casing?or?liner?tubulars. Buttress threads are square-cut and create a hydraulic seal through the interference fit of the mating threads
Schlumberger Ltd. (The World's Leading Supplier Of Technology, Integrated Project Management And Information Solutions to Customers Working in The Oil and Gas Industry Worldwide), Schlumberger Oilfield Glossary Cedex, France 2014. http://www.glossary.oilfield.slb.com/en/Terms/sym/ a.aspx, (Ergo - Brit) {766}