Purple
Violet
noun
The kanji and the word are exactly the same. That means they share meanings as well.
You learned this reading of 紫 when you learned the kanji, so you should be good to go!
暗闇の中でキラキラ光る紫色の光を見た瞬間、「母だ」と思ったんです。
The instant I saw purple light shining through the darkness, I thought, "Mom."