This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
臞 combines ⺼ (flesh/body) with 瞿, which likely contributes the sound. The exact historical development is uncertain.
The flesh radical ⺼ suggests something related to the body, but the overall meaning is unclear. Think of it as a body-related character with an uncertain sense.
For ク, imagine a body part shaped like a 'Q' (cue): Q -> ク, though the meaning remains vague.