tri·bol·o·gy 
(trī-bŏlə-jē, trĭb-)
(trī-bŏlə-jē, trĭb-)n.
The science of the mechanisms of friction, lubrication, and wear of interacting surfaces that are in relative motion.
[Greek tribos, a rubbing; see TRIBOELECTRICITY + -LOGY.]
tri′bo·logi·cal (trī′bə-lŏjĭ-kəl, trĭb′ə-) adj.
tri·bolo·gist n.