underbody vs underneath

underbody

• The underside of a vehicle. 

• The underparts of a bird or animal. 

underneath

• The lower surface or part of something. 

• A background radio sound track played during a specific announcement or program. 

• Under the control or power of. 

• Under, below, beneath. 

• Under, lower. 

• On the underside or lower face. 

• Below; in a place beneath.