The term BIZ ABBR. is an abbreviation for business abbreviations. The three solutions to this crossword are CORP (4 letters), CO (2 letters), and INC (3 letters). CORP stands for corporation, which is a legal entity that is separate from its owners and can be taxed, sued, and held liable for debts. CO stands for company, which is a business organization that is owned by one or more people and is typically involved in commercial activities. INC stands for incorporated, which is a type of business structure that provides limited liability protection to its owners.