1to stick
2to paste
3to post (e.g. on a blog)
4to keep close to
5to fit snugly
6to subsidize
7allowance (e.g. money for food or housing)
8sticker
9classifier for sticking plaster: strip
Examples
wǒ我wàng jì忘记zài在xìn fēng信封shàng上tiē贴yóu piào邮票le了。
我忘记在信封上贴邮票了。
I forgot to attach a stamp to the envelope.
门外又被贴满了小广告。
Everything outside is fly-posted again.
把邮票贴在信封上。
Stick a stamp on the envelope.