Time, Hour
noun
The kanji and the word are exactly the same. That means they share meanings as well.
とき
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: What time is it? It's time to key (とき) your enemy's car. Imagine yourself looking at your watch, waiting until the correct time to perform a synchronized keying of someone's car. Who do you hate the most? Whose car would you like to key?
あの時、父は五十才だったと思います。
At that time, I think my father was 50 years old.
小さかった時、何かスポーツはしていましたか？
Did you do any sports when you were little?
「時を止めて下さい」と天を向いて言いました。
"Please stop the time," he said towards heaven.