Public international law

The second entry is l’égalité souveraine, and its adjective is the same word as the English « sovereign », minus a letter that was never meant to be there. Both go back to a Late Latin superanus, the one placed above, built on super. Old French made it soverain, English borrowed it in roughly that shape, and for a long time wrote it with no g in sight. The letter came later, when writers took the last syllable for « reign », which is after all what a monarch does, and spelt it accordingly. The guess was wrong and the spelling stuck. « Foreign » went through the same accident: it is forain, from foranus, out of doors, and it caught its g by the same false analogy. French kept both words clean and sent them in very different directions. Souverain still means supreme, as in un remède souverain or le souverain pontife, while forain ended up at the fairground, in la fête foraine and un marchand forain. So when a treaty speaks of sovereign equality, the French spelling is both the older one and the one that tells the truth about the word.