Word Study
regnal
CIDE DICTIONARY
regnal, a. [L. regnum reign.].
Of or pertaining to the reign of a monarch; as, regnal years. [1913 Webster]
OXFORD DICTIONARY
regnal, adj. of a reign.
Idiom
regnal year a year reckoned from the date or anniversary of a sovereign's accession.
Etymology
AL regnalis (as REIGN)
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