When a beverage is referred to as "austere" it is usually meant to say that the beverage is a bit stern or severe. Other descriptors often used interchangeably include, "tight" or "closed". It is usually used to indicate high tannin and acidity that will improve with age or decanting. Some use the term austere not in reference to its tannins or "tightness" but to imply a beverage that may be more challenging to embrace hedonically. (Wine,Beer,Spirits,Sake,Mead/Tasting Terms)