to rein in / to compel / to force / to carve / to engrave / (literary) to command / to lead / bridle / (physics) abbr. for 勒克斯[le4 ke4 si1], lux
勒
=
力
+
革
:
Sir Lancelot (l) constructed a mechanical bull in the elevator's bathroom (e4), mainly just using a cow's hide (革) and a power button (力). To rein in (勒) the wild mechanical bull he presses the button and rides the bull again and again.