To Paste, To Stick
godan verb
Because the hiragana ends with an う sound, you know this word is a verb. The kanji itself means paste so the verb vocab is to paste (or to stick).
はる
The reading is the same as the one you learned with the kanji.
肩がこったので、湿布を貼りました。
I have stiff shoulders so I put a compress on them.