The term 'ADDITION SIGN' can be represented by two different crossword solutions: CARET (5 letters) and PLUS (4 letters). The caret symbol, also known as the circumflex, is a V-shaped symbol that is commonly used in mathematics to denote addition. The PLUS sign is a symbol that is used to indicate the operation of addition, as well as a positive quantity or number. Both symbols are widely used in mathematics and other fields to represent the concept of addition.