A compiler is distinguished by the fact that it produces 'object code' as output and does not execute it (though some options may exist to run further programs afterwards). Before execution is performed, all object files that make up the program need to be linked together, before the resulting executable memory image can be loaded into memory for execution.

Conversely, a scripting language is a sort of slang for using a type of interpreted language that under unix and linux can select its interpreter program that will actually execute after reading the script into memory, via the special "comment" on the first line, e.g.

#!/usr/bin/perl
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When executing such a Perl script and examining what programs are running in memory before it finishes, (e.g. in unix with the ps command) you will find that the Perl interpreter specified in this magic line is running, not your Perl script or any compiled or linked by-product of it and this demonstrates that it has not been compiled.

Update: BUT Perl becomes a compiler or cross-compiler if it is used to generate object or C-code for eventual loading or linking by another program rather than executing the source at once. So one could argue it is everything it can do: a scripting language, a compiler, an interpreter...