sound / Short for 音読み (on'yomi): the Chinese-derived reading of a kanji / (by extension) reading of a Chinese character outside the Japanese language; rime / Short for 音楽 (ongaku): music

(anatomy) a pectoral muscle

(Internet slang) Short for 胸が熱くなる.

a badge, an insignia worn on the chest

(anatomy, uncommon, dated) cephalothorax

full breasts / boob job, breast augmentation surgery

(figuratively, idiomatic) heart pounding; butterflies in one's stomach

(idiomatic) a more powerful person partners with a less powerful person, such as for practicing

(idiomatic) to be unsettled, to be uneasy

to have a lump in one's throat, stomach full of food / (idiomatic) to be emotionally moved