Definition of "overdressed"

Almost all babies get heat rash during hot weather. However, heat rash can occur even in cold weather if your child is overdressed either during the daytime or the nighttime.

1994, Ira J. Chasnoff, “Heat Rash”, in Your Child: A Medical Guide, page 297

Not, a thousand times not, that she should be overdressed. An overdressed Angel is a contradiction in terms. We associate not angelic attributes with the gorgeous attire and plenipotent jewellery of a Houndsditch Hebrewess. Just as the man who is got up in the loudest of loud costumes, and hangs out as a sort of Christmas tree, with incongruous braveries and charms and nicknacks pendent all over, we are apt to deem not a gentleman, but a gent.

1870 October, Perceval Picard, “House Angel in Trim Array”, in The New Monthly Magazine, volume 147, number 598, page 387

"I was worried you might think I am overdressed," Sheinna replied in a small voice.

2012, Barbara Cartland, Love and the Clans (The Pink Collection; 89)