azuring

Verb

azure (third-person singular simple present azures, present participle azuring, simple past and past participle azured)

1. (transitive) To colour blue.
   • Our readers are aware that much of the sugar sold in many countries goes through an azuring treatment; blue is added to granulated sugar with the view of making it appear whiter than it actually is.1907, The Sugar Beet, volume 28, page 271

See all 11 meanings of azure