The term 'Basis of REASONING' can be broken down into two words: 'PREMISE' and 'REASONING'. PREMISE is a seven-letter word meaning a proposition or statement that serves as the basis for an argument or inference. REASONING is the process of using logic to draw conclusions from given information. Together, these two words form the term 'Basis of REASONING', which refers to the fundamental principles used to form logical arguments and draw valid conclusions.