The term "axillary" refers to the armpit area. It is derived from the Latin word "axilla," which means armpit. The other options, tarsal, acromical, and thoracic, do not specifically relate to the armpit. Tarsal refers to the bones in the foot, acromical relates to the acromion process of the scapula, and thoracic refers to the chest area. Therefore, "axillary" is the correct answer as it is the term that specifically describes the armpit.