to exhale; to breathe outLiterally, “to let out breath.” It refers to breathing out or exhaling. The term can also appear in descriptions of the sound or action of exhaling, such as (息を吐く音) (“the sound of exhaling”).
JA: 寒い日に息を吐くと、自分の息が見えるんだよ。
EN: When you exhale on a cold day, you can see your own breath.