An XML format for describing network services as a set of endpoints operating on messages containing either document- oriented or procedure-oriented information. WSDL complements the UDDI standard by providing a uniform way of describing the abstract interface and protocol bindings and deployment details of arbitrary network services.
Sources:
NIST SP 800-95
from
Web Services Description Language (WSDL) 1.1, Oregon Statewide Automated Child Welfare Information System (SACWIS) Glossary