stick ‧ er /ˈstɪkə $ -ər/ BrE AmE noun [countable]
[ Word Family: adjective : ↑ sticky , ↑ stuck , ↑ unstuck , ↑ non-stick ; noun : ↑ sticker , ↑ stickiness ; verb : ↑ stick ]
a small piece of paper or plastic with a picture or writing on it that you can stick on to something ⇨ label :
Children get stickers for good work.
bumper sticker (=a sticker on the back of a car)