Glue language

Glue language is just a term used to describe a scripting language that's useful for (and maybe even optimized for) running other programs, taking their output, massaging it, sending it off to another program, and so on. You're "gluing" a bunch of command line apps together by taking output from one and piping it to another.

Shell scripting (like bash) can be considered a glue language. Perl is another.