Another solution is to use a loop and push the words into an array as you get them. The user enters a blank line to stop entering words. This had the advantage that the user can input complete phrases.

use strict;
use warnings;

my @words;
my $i = 1;
while (1) {
  print "Enter word $i: >> ";
  $i++;
  chomp (my $word = <>);
  last unless length $word;
  push @words, $word;
}
print join(",", @words);
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