This character is made of the front shape of human being.it has meaning of big ,wide,long.We often pronounce dai.
This kanji is often used for the term of Dai ginjo or Jyunmai dai ginjo which are categories of sake.The difference between Dai ginjo and just Ginjo is the polish ratio. If dai is added front, the polish ratio smaller. That means bigger part of outside of rice is removed.
Legally, Dai ginjyo or Jyunmai dai ginjo should have less than 50% of polished ratio ,compared to 60 % of Ginjo or Jyunmai ginjo.