open source

adjective

1. Computers. pertaining to or denoting software whose source code is available free of charge to the public to use, copy, modify, sublicense, or distribute.
2. pertaining to or denoting a product or system whose origins, formula, design, etc., are freely accessible to the public.

noun

1. 1. intellectual property, esp computer source code, that is made freely available to the general public by its creators
   2. (as modifier)open source software Compare closed source

1. Relating to source code that is available to the public without charge. Open-source code is often enhanced, improved, and adapted for specific purposes by interested programmers, with the revised versions of the code are made available to the public. For example, most of the code in the Linux operating system is open-source.