This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
娞 combines 女 (woman) with 妥, which likely contributes the sound. The exact historical development is uncertain.
A woman 女 beside 妥, a shape associated with peace or settling. Picture a woman bringing calm and elegance to a scene.
For ダイ, imagine a woman named Dai who radiates calm elegance: Dai -> ダイ.