(1) A public standard for connecting hardware to hardware and software to software. With regard to hardware, it implies that there is more than one brand of product that can be hooked up to the device with the open interface. In the case of software, it implies that more than one program exists to interface with the application that has the open interface or that a program can be readily written to communicate with it. See open system and open standard.
(2) (Open Interface) A library of routines for expanding the Insight II molecular modeling program from Accelrys Software, San Diego, CA (www.accelrys.com).