Royal is the French middle rung between native kingly and Latin regal. English took it in the mid-1200s from Old French roial, which is Latin regalis worn down by several centuries of French speech — the g gone, the vowels reshaped.
That makes royal and regal the same Latin word arriving twice by different routes, and the pair is a neat demonstration of what French does to Latin: it erodes it. Where Latin has regalis, French has roial; where Latin has fragilis, French has frele, which English took as frail while also taking fragile straight from the Latin. English then keeps both and assigns them different registers. Battle royal, from the 1670s, preserves the French habit of putting the adjective after the noun, like attorney general.
royal (adj.) mid-13c., "fit for a king;" late 14c., "pertaining to a king," from Old French roial "royal, regal; splendid, magnificent" (12c., Modern French royal ), from Latin regalis "of a king, kingly, royal, regal," from rex (genitive regis ) "king," from PIE root *reg- "move in a straight line," with derivatives meaning "to direct in a straight line," thus "to lead, rule." Of institutions, "founded under the patronage of a sovereign" (c. 1500). The meaning "splendid, first-rate" is by 1853. The U.S. colloquial use as an emphasizer, "thorough, total" is attested from 1940s. Battle royal (1670s) preserves the French pattern of adjective after noun (as in attorney general ); the sense of the adjective here is "on a grand scale" (compare pair-royal "three of a kind in cards or dice," c. 1600). Royal Oak was the name given to the tree in Boscobel in Shropshire after Charles II hid himself in it during flight from the Battle of Worcester in 1651. Sprigs of oak were worn to commemorate his restoration in 1660. also from mid-13c. royal (n.) "royal person," c. 1400, from royal (adj.). Specifically "member of the royal family" from 1774, colloquial. also from c. 1400
royal came in through Norman French, and its spelling follows that family's conventions.
On the register ladder
English kept all three words for this idea, one from each layer, and the rung is itself the cue: the native word is blunt and concrete, the French one polite, the Latin one formal or technical.
| Old English | French | Latin |
|---|---|---|
| kingly | royal | regal |
Norman French in the spelling guide · guess another word's family