I am a board certified anatomic and clinical pathologist with sub-specialty training in molecular genetic pathology.
Pathology comes from the Greek word pathos (disease). Pathology is the study of disease.
For those who are not familiar with pathology, we basically have two branches: Anatomic Pathology (AP) and Clinical Pathology (CP). Anatomic includes surgical pathology (includes frozen sections or intraoperative consultations), autopsy (forensics), cytology (includes pap smears and fine needle aspirations), etc. I think of Anatomic Pathology as, you get a chunk of tissue. Now diagnose it!
Clinical pathology is also known as "Laboratory Medicine." It includes chemistry, blood banking or transfusion medicine, molecular pathology, microbiology, etc. When you go to a doctor, and he or she orders a bunch of tests (e.g., urinalysis, blood draws), they will likely go to a clinical pathology laboratory. Pathologists interpret the lab results in their clinical context.
My sub-specialty is molecular genetics, which involves understanding, performing tests for, and interpreting the genetic material (DNA) that makes us who we are as human beings and causes diseases such as cancers and hereditary conditions.