This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
侹 combines 亻 (person) with 廷, which likely provides the sound. The exact historical meaning is uncertain.
A person 亻 beside 廷, a shape associated with a court or hall. Without a clear meaning, picture a lone figure standing in an empty hall, their purpose unknown.
For テイ, imagine the person in the hall holding a tea tray: tea -> テイ, but the scene remains mysterious.