IPA: /əˈdɔːrnər/
KK: /əˈdɔrnər/
A person who adds decorative items or embellishments to something, making it more attractive or beautiful.
The adorner carefully selected jewels to enhance the beauty of the dress.
Adorner is formed from "adorn" (from Old French *adorner*, meaning to decorate or embellish) and "-er" (meaning a person who). An adorner is a person who decorates or embellishes something.
Think of someone who 'decorates' ('adorn') — the '-er' just means a person. An adorner is someone who adds beauty or decoration.