These grapes are seedless, so they are easy to eat.
It was, without a doubt, the perfect speech.
Could you cancel this deal for now?
This is the noun version of the kanji nothing, so when you have nothing, you are without.
Since this word consists of a kanji with hiragana attached, you can bet that it will use the kun'yomi reading. You didn't learn that reading with this kanji, so here's a mnemonic to help you:
When you are without you don't have anything to eat either, so you end up gnashing (なし) your teeth together instead.