Cotton Plant, Cotton Material
independent noun, in compounds
The kanji and the word are exactly the same. That means they share meanings as well.
わた, めん
The reading can be either the kun'yomi or on'yomi reading, so you have a choice there. Let's learn the わた reading, though. Just think what (わた) is cotton? What is it? What does it mean? Ask a lot of "what" questions about cotton to yourself.
綿菓子が大好きなんです。
I love cotton candy.
手芸用の綿はどこで買えますか？
Where can I buy cotton material for handicrafts?
ヌイグルミから綿がはみ出ている。
The cotton is sticking out of this stuffed animal