"Stream of Conciousness" :-) You can use rambling English here, if you show some code demonstrating your problem. I think what you want to do is specify a font size. Check out Tk::FontDialog.

#!/usr/bin/perl
use warnings;
use strict;
use Tk;

my $mw = new MainWindow;

$mw->fontCreate('big',
   -family=>'courier',
  -weight=>'bold',
  -size=>int(-18*18/14));

$mw->fontCreate('medium',
   -family=>'courier',
   -weight=>'bold',
   -size=>int(-14*14/10));


my $entry = $mw->Entry(-font =>'big',
                 -text=>'Big')->pack();
my $entry1 = $mw->Entry(-font medium',
                 -text=>'Big')->pack();

MainLoop;
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