Letter
noun, の adjective
A hand paper is a letter because letters are generally written by hand on paper.
If you want a more graphic image, imagine writing a letter on your hand, and how much it would hurt to chop off your hand and send it.
てがみ
The reading is double kun'yomi (body parts tend to make kanji in words change to a kun'yomi reading). Both kanji in this word had you learn that reading right from the start, though, so you should be able to read this word. Just watch out for the rendaku making it がみ, not かみ.
外国に手紙を出しました。
I sent a letter to a foreign country.
その金正日からの手紙、ネットオークションに出しちゃえば？きっとだれかしらかうと思うよ。
Why don't you put up the letter from Kim Jong Il for online auction? I think somebody would buy it.
私はコカコーラ宛に、心のこもった手紙を書いて、どうして彼らの製品にたくさん砂糖が入っているのかについて尋ねたいと思います。
I’m going to write a very heated letter to Coca-Cola and ask why there is so much sugar in their products.