This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
磿 combines 厤 with 石 (stone). The exact historical development is uncertain, but it likely relates to stone or rock in some way.
The outer shape 厤 encloses a stone 石, suggesting something related to stone or a rocky place, but its meaning is unclear.
For レキ, imagine a rocky ledge (レキ) where the stone 石 sits under the outer enclosure 厤: ledge -> レキ.
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