reversion vs reversal

reversion and reversal both are nouns.

Word	Noun	Adjective	Verb	Adverb
reversion	Yes	No	No	No
reversal	Yes	No	No	No

As nouns, reversion and reversal are synonyms defined as:

Other synonyms of reversion include reverse, turnabout, turnaround.

As nouns, reversal is a hypernym of reversion; that is, reversal is a word with a broader meaning than reversion:

reversion (noun)	reversal (noun)
a failure to maintain a higher state	a change from one state to the opposite state
turning in the opposite direction	the act of reversing the order or place of
returning to a former state	turning in the opposite direction
(genetics) a return to a normal phenotype (usually resulting from a second mutation)	a major change in attitude or principle or point of view
a reappearance of an earlier characteristic	a judgment by a higher court that the judgment of a lower court was incorrect and should be set aside
(law) an interest in an estate that reverts to the grantor (or his heirs) at the end of some period (e.g., the death of the grantee)	a decision to reverse an earlier decision
	turning in an opposite direction or position
	an unfortunate happening that hinders or impedes; something that is thwarting or frustrating