In threading, what does the term "crest" refer to?

The term "crest" in threading refers specifically to the top-most point of the thread. This terminology is essential for understanding the geometry of threaded fasteners. The crest represents the highest area on the outer surface of the thread profile, which is crucial for ensuring proper fit and engagement in threaded applications. Understanding the crest's position relative to other thread features, like the root (the lowest point), helps in specifying tolerances and ensuring that threads are manufactured correctly for effective performance under load. The crest is vital for the functionality of a threaded connection as it affects the mating with corresponding threads and overall structural integrity.