brilliant

the word 'brilliant' entered english in the late 17th century from the french brillant, meaning 'shining'. the french term derived from the italian brillare ('to sparkle'), whose origin is debated but is often linked to the latin beryllus, referring to the precious beryl gemstone known for its sparkle. this literal connection to gleaming gemstones provided the semantic foundation. over time, the meaning expanded metaphorically from describing physical radiance to signifying exceptional mental sharpness or outstanding quality, much like a gem standing out for its brilliance.

Structure: brill (shine) + iant (adjective suffix) brill (from french brillant, present participle of briller 'to shine', from italian brillare, possibly of onomatopoeic origin or from latin beryllus 'beryl', a gemstone). iant (a common anglicized adjectival suffix from french -ant, from latin -antem, present participle ending).