To Chant
transitive verb, ichidan verb
Because the hiragana ends with an う sound, you know this word is a verb. The kanji itself means chant so the verb vocab version is to chant.
Really, when you are going to chant, the most important thing to do is to figure out your tone (とな). If you get the tone down, the rest comes naturally.
背の高い魔法使いが呪文を唱えると、辺りは一瞬真っ暗になった。
When the tall wizard uttered the magic word, there was a moment of total darkness.