lustre n.

"gloss, radiance, quality of shining by reflecting light," 1520s, from French lustre "gloss, radiance" (14c.), common Romanic (cognates: Spanish and Portuguese lustre, Rumanian lustru, Italian lustro "splendor, brilliancy"), a noun ultimately from Latin lustrare "spread light over, brighten, illumine," which is related to lustrum "purification" (from PIE *leuk-stro-, suffixed form of root *leuk- "light, brightness").

Especially "quality of glossiness or radiance in a textile material or fabric." Figurative meaning "radiant beauty" is from c. 1600; that of "splendor, renown" is from 1550s. Lusterware, also lustre-ware, "stoneware or crockery having surface ornamentations in metallic colors," is attested by 1820.

word-ending that sometimes distinguish British from American English. In the U.S., the change from -re to -er (to match pronunciation) in words such as fibre, centre, theatre began in late 18c. and became standard there over the next 25 years at the urging of Noah Webster (the 1804 edition of his speller, and especially his 1806 dictionary). The -re spelling, like -our, however, had the authority of Johnson's dictionary behind it and was unmoved in Britain, where it came to be a point of national pride, contra the Yankees.

Despite Webster's efforts, -re was retained in words with -c- or -g- (such as ogre, acre, the latter of which Webster insisted to the end of his days ought to be aker, and it was so printed in editions of the dictionary during his lifetime). The -re spelling generally is more justified by conservative etymology, based on French antecedents. It is met today in the U.S. only in Theatre as an element in the proper names of entertainment showplaces, where it is perhaps felt to inspire a perception of bon ton.