This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
The exact historical development of 晫 is uncertain. It combines 日 (sun) with 卓, but the original meaning and component relationship are unclear.
The sun 日 beside 卓 might suggest a bright or clear day, but the meaning is not confirmed. Treat it as a rare kanji with an unknown meaning.
For タク, imagine a tack shining in the sun: tack -> タク, and the sun 日 makes it gleam.