IDL may refer to:
Computing Interface description language, any computer language used to describe a software component's interface IDL specification language, the original IDL created by Lamb, Wulf and Nestor at Queen's University, Canada OMG IDL, an IDL standardized by Object Management Group selected by the W3C for exposing the DOM of XML, HTML, CSS, and SVG documents Microsoft Interface Definition Language, an extension of OMG IDL for supporting Microsoft's DCOM services Web IDL, a variation of an IDL for describing APIs that are intended to be implemented in Web browsers Interactive Data Language, a data analysis language popular for science applications ICAD Design Language, a knowledge-based engineering language used with the software ICAD
Places John F. Kennedy International Airport, formerly named Idlewild Airport with IATA airport code IDL Indianola Municipal Airport, by FAA airport code Inner Dispersal Loop, the common name of Interstate 444, a highway in downtown Tulsa, Oklahoma
Other uses Islamic Democratic League, a party International Date Line, the time zone date boundary Intermediate-density lipoprotein International Drivers License International Dance League International Darts League, a defunct major darts tournament IDL Drug Stores, a now-defunct independent drug store cooperative Internet Defense League, a website