(Sanskrit) Action, activity; comes from kri, the same root as the word karma, which also means action. Kriya is related to physical matter and senses.
"How foolish we are! We often think that we never do all the foolishness and perversities that we see others do; this is why we arrive at the conclusion that we are magnificent persons. Unfortunately, we do not see the foolishness and wretched things we do."