2017-02-19 12:34 GMT-03:00 Alexandre Torres Porres <porres@gmail.com>:

But I've never seen people referring to, for example, the freeverb~ external as the "freeverb~ library".

So I checked freeverb~'s readme just to see how it referred to itself, here's the description

freeverb~ version 1.2
	reverb external for Pure Data and Max/MSP
	written by Olaf Matthes <olaf.matthes@gmx.de>