Ctags allows jumping to definitions/references.
Ctags allows you to generate tag files supported by several editors, including Emacs, Vi(m) and Atom.
These reg-exes are tested with universal-ctags (recommended), but should also work with exuberant-ctags (unmaintained).
Put the tags definitions in ~/.ctags.d/ or ./.ctags.d/ if you are using universal-ctags, or in the file ~/.ctags or ./.ctags if using exuberant-ctags.
To generate a TAGS file for Emacs, run
ctags -Re .
In the root of the project. I can highly recommend projectile which makes this process easier along with many other niceties.
For Vi(m) and Atom, generate a tags file by the command
ctags -R .