Something or someone that's adorned is decorated or dressed up in some way, like your favorite shirt, adorned with sequins and glitter.
The adjective adorned is great for describing anything that's embellished or trimmed with decorations. You may prefer the look of a nearly bare Christmas tree, adorned only with tiny white lights, while your sister prefers copious amounts of tinsel and ornaments. Adorned comes from the verb adorn, and its Latin root adornare, which means "furnish or provide" and also "decorate."