HomeKnowledgeGlossaryCommunitySign in

ICD

Medical billing & coding glossary · all terms

Definition. The International Classification of Diseases, the World Health Organization’s system for classifying diseases and related health conditions; U.S. claims use designated clinical and procedure modifications.

You'll come across ICD while working the revenue cycle — from eligibility and claim submission to payment posting and denials. See the related terms below, or browse the full glossary and the Knowledge Hub.

Enrollment is open for October

The Medical Billing Diploma launches October 15, 2026. Enroll free now and we’ll email you when lessons open.

Enroll free for October →