置顶

置顶	zhì dǐng	to sticky (an Internet forum thread etc)
置	zhì	to install / to place / to put / to buy
顶	dǐng	apex / crown of the head / top / roof / most / to carry on the head / to push to the top / to go against / to replace / to substitute / to be subjected to (an aerial bombing, hailstorm etc) / (slang) to "bump" a forum thread to raise its profile / classifier for headwear, hats, veils etc