If you want to count all WORD occurrences within a string (but not within substrings), you can do the following using the goatse operator:

use strict;
use warnings;

my $string = 'How much wood could a woodchuck chuck if a woodchuck cou
+ld chuck wood?';
my $woodCount = () = $string =~ /\bwood\b/g;
print $woodCount; # prints 2
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Hope this helps!