This is the 537th most frequent Korean word.
미칠
"미칠" is a form of the verb "미치다," meaning "to reach," "to affect," or "to go crazy," depending on context.
In this sentence, "미칠" is used to mean "crazy" or "mad," emphasizing the extremity of the situation.
그 소리는 정말 미칠 정도로 시끄럽다.
That noise is really unbearably loud.
Here, "미칠" pertains to the act of "affecting" or "having an impact on something."
그의 결정은 경제에 큰 영향을 미칠 것이다.
His decision will greatly influence the economy.
In this context, "미칠" refers to the process of "losing one's sanity" due to someone's actions.