1. a language that is to be translated into another language;
WordNet (r) 3.0 (2006):
n 1: a language that is to be translated into another language
The Free On-line Dictionary of Computing (30 December 2018):
(Or "source", or rarely "source language")
The form in which a computer program (software) is written by
the programmer. Source code is written in some formal
programming language which can be compiled automatically into
object code or machine code or executed by an interpreter.
Source code might be stored in a source code management system.
If you have the source code for a program rather than just its
compiled, executable form, then you can, with the right tools,
modify it to fix bugs or add new features. This is the basis
of the open source philosophy - empowering people to improve the
software they use for the benefit of themselves and others.
The Jargon File would have us believe that an old-time hacker
might refer to source code informally as "English", with the
implication that to him his favourite programming language is at
least as readable as English.