This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
The exact historical development of 猤 is uncertain. It visually combines the animal radical 犭 with 癸, but the original semantic or phonetic role of 癸 in this character is unclear.
With no clear meaning, picture a fierce beast (犭) combined with the last of the ten celestial stems (癸), suggesting a wild, untamed energy that is hard to define.
For キ, imagine a key (キー) unlocking the cage of this mysterious beast: key -> キ, and the beast's true nature remains unknown.