This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
碲 combines 石 (stone) with 帝, which likely contributes the sound. The exact historical development is uncertain, and the character is rare.
The stone radical 石 beside 帝 suggests a type of stone or mineral, but without a known meaning, picture a mysterious stone tablet inscribed with an emperor's decree.
For テイ, imagine a tea (ティー) cup made of stone: tea -> テイ, and the stone cup holds the emperor's tea.
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