A small piece or scrap of paper; a slip of paper. Can also be used figuratively to mean a worthless piece of paper.
机の上に古い紙切れがいくつか落ちている。
There are several old scraps of paper on the desk.
彼に渡した契約書は紙切れ同然だと言われた。
I was told the contract I handed him was no better than a scrap of paper.
メモは小さな紙切れに書いて渡した。
I wrote the note on a small slip of paper and handed it over.