Hi IB2017

You may want to look into a so called 'lookahead' or 'lookbehind'. In the following example I use a 'Negative Lookahead' by specifying (?!\-)

use strict ;
use warnings ;
my @stopwords = qw{ sous } ;
my $string = "sous sous-alimentation" ;
my ($rx) = map qr/(?:$_)/, join "|", map qr/\b\Q$_\E\b(?!\-)/, @stopwo
+rds;
$string =~ s/$rx//g ;
print $string ;
__END__
 sous-alimentation
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Veltro

edit: Link: Extended Patterns