Complex sentence: Paranormal is a general term (coined c.1915--1920) that designates experiences that lie outside "the range of normal experience or scientific explanation" or that indicates phenomena understood to be outside of science's current ability to explain or measure.
Split into simpler sentences: Paranormal is a general term (coined c.1915--1920) used to define experiences that cannot readily be explained within "the range of normal experience or scientific explanation". The term may also be applied to phenomena outside of science's current ability to explain or measure.