difficult; hard to do; troublesome; not easy; problematic; the opposite of 容易 róng​yì

to cross over; to jump over; to climb over (a fence, mountain, etc.)

(literary) a boundary or restricted area; usually used in the phrase 不敢越雷池一步 bù​gǎn​yuè​léi​chí​yī​bù, meaning one must not overstep the mark