Meta Tag showing site name two times

Ok for the longest time my site would show up as zencart bla bla on google search. So I found out how to make it show up with my sites name in my 'includes' folder. I think I added my site in two many spots because my site come up with "My Site, My Site" in google when it should only say it once.
Where in here should I change that? MYSITE is my sites name

/ page title
define('TITLE','MYSITE');

// Site Tagline
define('SITE_TAGLINE','MYSITE');

// Custom Keywords
define('CUSTOM_KEYWORDS', 'ecommerce, open source, shop, online shopping');

// Home Page Only:
define('HOME_PAGE_META_DESCRIPTION', '');
define('HOME_PAGE_META_KEYWORDS', '');

// NOTE: If HOME_PAGE_TITLE is left blank (default) then TITLE and SITE_TAGLINE will be used instead.
define('HOME_PAGE_TITLE', ''); // usually best left blank

Also do I need to add meta tags somewhere in here to help people find what my site sells. Like if I sold shoes do I put "shoes" somewhere