There's no sharp border between a compiler and and an interpreter. As you said, we often think of a compiler that takes the entire source code, and produces something else (typically, before running it), while an interpreter just looks at a small chunk of the source at a time, and executes that before carrying on.

But compilers typically produce output that's being "interpreted". Machine code is basically "interpreted". And a language that has the ability to use "eval", can defer most of its "compilation" to runtime, and have it compiled one chunk at a time.

I usually call a program that takes data in one format and produces equivalent data in another format a compiler. That means that 'gcc' is a compiler. But also 'dvips'. And perhaps parts of 'perl' as well, although the other format is only used internally.

Abigail