March 18, 2026
The Pathology Dictionary provides simple, patient-friendly definitions of the most common words and phrases used in pathology reports. Each entry explains what a term means in plain language and how pathologists use it. There are currently over 500 terms in the dictionary, covering everything from basic concepts like biopsy and malignant to specialized tests like immunohistochemistry and FISH.
If you are looking for a detailed explanation of a specific diagnosis rather than a single term, visit our Diagnosis Guides. You can also ask Osler, our pathology chatbot, to explain any term or finding from your report in plain language.
Use the alphabet bar below to jump directly to any letter, or scroll through the dictionary at your own pace.
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