(Health Level 7) ANSI-accredited standards for electronically defining clinical and administrative data in the healthcare industry from Health Level Seven International (www.hl7.org). HL7 provides standards for messaging, electronic records, decision support queries, medicine labels and the visual integration of data from different applications (see CCOW). The "7" in the name comes from application layer 7 in the OSI model, which is the highest level where programs talk to each other. HL7 does not deal with the lower levels of the OSI model, which are the transport and network protocols. See healthcare IT and OSI model.