in·tra-aor·tic balloon counterpulsation \¦in.trə(ˈ)ā¦ȯr|d.ik, -ȯ(ə)|, |tik, -ēk, -trä-\noun : counterpulsation in which circulatory assistance is provided by a balloon inserted in the thoracic aorta which is inflated during diastole and deflated just before systole