RING STRAIN

'Ring strain' is an organic chemistry term that describes the destabilization of a cyclic molecule—such as a cycloalkane—due to the non-favorable high energy spatial orientations of its atoms. Non-cyclic molecules do not exhibit ring strain because their terminal (end) atoms are not connected to force a particular type of spatial orientation.
The ring strain is a combination of angle strain or Baeyer strain, conformational strain or Pitzer strain and transannular strain or van der Waals strain.