Breath
noun
The kanji and the word are exactly the same. That means they share meanings as well.
いき
Since this word is made up of a single kanji, it should use the kun'yomi reading. When learning the kanji, you didn't learn that reading, so here's a mnemonic to help you with this word: You smell someone's icky (いき) breath. It's gross. Your skin crawls and your eyes roll back in your head from the icky, icky smell. You might die.
あんたの息、死ぬほどくさいよ。
Your breath is so stinky that I could die.
びっくりしすぎて、息が止まるかと思ったよ。
You knocked the breath out of me!
そんなに走り回ったら息が切れるよ！
If you run around that much, you'll be out of breath!