Elusive
Part of speech: adjective
Definition: evading capture, comprehension or remembrance rarely seen difficult to describe
Example sentence: Diet is weird. It's elusive. I just try to listen to my body.
Subtle
Part of speech: adjective
Definition: Hard to grasp; not obvious or easily understood; barely noticeable.Cleverly contrived.Cunning, skillful.insidiousTenuous; rarefied; of low density or thin consistency.
Example sentence: But the relationship of morality and power is a very subtle one. Because ultimately power without morality is no longer power.