in reply to Best approach to creating a regex from a filehandle

You can probably avoid map by using
'(?:' . join(')|(?:', @blacklist_words) . ')'

But, if the "words" can contain non-alphabetical characters with special meaning in regexes, you might need to map quotemeta to each word.

لսႽ† ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ