Limit
Limitations
noun, の adjective
As you reach the limit of your world, you face your limit and confront your limitations.
This word refers to the maximum extent or limit that something can reach or endure. It conveys the idea of reaching the utmost point beyond which a situation or condition cannot be sustained.
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.
限界を決めるのは、いつも自分自身なんですよ。
The one who sets the limits is always yourself.
仕事で限界まで自分を追いつめてしまい、今はちょっと休みを取っています。
I am taking a little break from work now because I ran myself into the ground.
その野球選手は、自分の限界を感じて引退した。
The baseball player retired when he felt that he had reached his limit.