use strict;

my $wordOne = 'longwordOne';
my $wordTwo = 'anotherLongWord';
my $wordThree = 'thirdLongHere';

while (<DATA>) {
next if ($_ =~ /(?:$wordOne|$wordTwo|$wordThree)/gi);

  print ;

}

exit;


__DATA__
blah blah longwordOne blah
blow
blow
blee anotherLongWord glgl
thirdLongHere
fddsf ds sdfs fs fsd
  fggh hg longwordOne
sdasd

##</code><code>##

blow
blow
fddsf ds sdfs fs fsd
sdasd

##</code><code>##

next if /$wordOne|$wordTwo|$wordThree/i;