The term 'Kind of Barrier' can be solved by two crossword solutions: SONIC (5 letters) and SOUND (5 letters). SONIC barriers are physical objects that block SOUND waves from passing through them, such as walls or fences. SOUND barriers are also physical objects, but they are designed to absorb SOUND waves rather than block them, such as acoustic foam. Both SONIC and SOUND barriers are used to reduce noise pollution in residential and commercial areas.