Mendoza line noun2 •A .200 batting average, which is around the minimum batting average a player with strong defensive skills can have and still stay in the major leagues. Named for Mario Mendoza.His recent slump has put him perilously close to the Mendoza line; he may be headed to AAA soon. •The line dividing acceptable mediocrity from unacceptable mediocrityI don’t think you could find any other figure in politics who has run this far below the Mendoza line and still managed to get taken seriously.A sub-$2,000 per theater average... is the Mendoza Line of box office numbers.