What is the meaning of the combining form "phren/o"?

The combining form "phren/o" specifically refers to the mind. This terminology is often used in medical contexts related to mental health and conditions involving cognition. For instance, the term 'phrenology' historically referred to the study of the structure of the skull as a determinant of character and mental abilities, illustrating the link between the mind and psychological characteristics.

The other options represent different concepts in medical terminology. The combining form that denotes "body" is typically "somat/o," while "pleura" refers to the membranes surrounding the lungs, and "pineal gland" specifically relates to the small endocrine gland in the brain that produces melatonin. Understanding these distinctions reinforces the meaning of "phren/o" as it pertains uniquely to the mind in medical language.