Other forms: 素適、素的、ステキ
adjectival nouns or quasi-adjectives (keiyodoshi)
1.lovely; wonderful; charming; enchanting; nice; great; splendid; marvellous (marvelous); fantastic; superb
あなた達とおるは本ほん当とうに素敵すてきなお客きゃくだ。
You're such a lovely audience.
Mrjisho