Chest
Breasts
noun
The kanji and the word are exactly the same. That means they share meanings as well.
This vocab word uses the same reading as the one you learned with the kanji. At least I won't have to bring up the image of you mooning (むね) people with your breasts or whatnot. Oh dang, I just went and did it.
あの人のことを思うと、胸が苦しいんです。
When I think of that person, my heart aches.
私は右胸にホクロがあります。
I have a mole on my right chest.
どうして首になったかって？それはご自身の胸に聞いてみてはいかがですか？
Why did you get fired? Perhaps you should ask your own conscience about that.