noun which may take the genitive case particle 'no'
A direct loan from English 'ardent', used as a no-adjective to describe intense enthusiasm, passion, or devotion. Common in formal or literary contexts, often modifying abstract nouns like 支持 (support) or 愛 (love).
彼はアーダントな支持者だ。
He is an ardent supporter.
アーダントな愛を捧げる。
To offer ardent love.