[smusamashah]

Found it on C2 wiki. It's not exactly the same definition as in the linked article though.

  Also, referred to as a "steel thread". Runs the length of the application architecture (front-to-back, top-to-bottom, whatever) of what you are building. Each new top-to-bottom feature is a new thread. Steel threads wrapped together incrementally form a cable stronger than an equivalent diameter solid cable extruded all at once. Thread akin to string, as in string testing. - NormanECarpenter

https://wiki.c2.com/?SpikeSolution (too bad the c2.wiki has modernized the UI, its now almost unusable)