The term COMPLETELY OPPOSITE can be described by two crossword solutions: POLAR (5 letters) and POLESAPART (10 letters). The word POLAR is derived from the Greek word 'POLARIS' which means 'of or near the pole'. This refers to the two opposite points on a sphere, such as the North and South Poles. The phrase 'poles apart' is an idiom that means two things are completely different or opposed to each other. Therefore, both of these crossword solutions accurately describe the term COMPLETELY OPPOSITE.