The term 'Walking UNIT' can be broken down into two words, 'STEP' and 'UNIT'. STEP is a 4 letter word which can refer to the action of moving one foot at a time in a particular direction. UNIT can refer to a single thing or person, or a group of things or people that are part of a larger whole. Therefore, the term 'Walking UNIT' could refer to a single person or group of people who are walking together in a particular direction.