You are printing the return value of s///, which is the number of substitutions made. If there was only 1 substitution, it prints 1, which just happens to match the hash value. You should print $_ instead: 
use warnings;
use strict;

my %words = (word => 1, word2 => 1, word3 =>1);
my $temp  = 'WORD2';
my $temp1 = 'word2';
$_ = 'here is word2';
s/$temp1/$words{$temp1} ? "$temp " : "[$temp] "/ex; 
print "$_\n";

__END__

here is WORD2

[download]

In reply to Re: help with a regex by toolic
in thread help with a regex by jms53

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