##  [Trunnion](/trunnion) 

  ##  [Trunnion](https://engineering.quantumdictionary.io/trunnion-0) 

  

 [![Engineering & Applied Technologies Dictionary](/sites/default/files/styles/large/public/2026-01/Engineering%20%26%20Applied%20Technologies.png.webp?itok=_IKO7_-n)](/topic-specific-dictionaries/engineering-applied-technologies)



**Engineering & Applied Technologies Dictionary**

 







 

 

 

 



 

 

 

 

Definition

A cylindrical projection, boss, or mounting surface designed to act as a pivot or journal on which a component rotates or is supported; configured to bear radial (and sometimes axial) loads through a bearing interface or direct contact, and commonly integrated into housings, shafts, or structural elements to locate rotational motion.