A 
cordial is any invigorating and stimulating preparation; as, a peppermint cordial. The term derives from obsolete 
medical usage, as various beverages were concocted which were believed to beneficial to one's 
health, especially for the heart (
cordialis, Latin). 
Alcoholic cordials are also known as liqueurs.
In Australia, 'cordial' is an extremely sweet (usually entirely artificial) non-alcoholic drink concentrate that you mix with water to taste.
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