Histology: The study of the form of structures seen under the microscope (light, electron, infrared ). Also called microscopic anatomy, as opposed to gross anatomy which involves structures that can be observed with the naked eye. The word "anatomy" comes from the Greek ana- meaning up or through + tome meaning a cutting. Anatomy was once a "cutting up" because the structure of the body was originally learned through dissecting it. The word "histology" came from the Greek "histo-" meaning tissue + "logos", treatise.
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Medically reviewed by Martin Zipser, MD; Board Certified: Surgery