(rare) Tending to vacillate.

(law) A year in the reign of a monarch, beginning on the day of accession, the set of which are numbered ordinally. Formerly laws in the United Kingdom were identified in part by the regnal year of...

An image of an object as seen by the naked eye, without magnification. / An image of an object that is at least as large as the object.

present participle of 404