lizard
蝪 centers on a lizard, a small reptile. The meaning is specific and concrete, with no clear extended senses.
蝪 combines 虫 (insect/reptile) with 昜, which likely contributes the sound. The exact historical development is uncertain.
The left side 虫 suggests a creeping creature, and the right side 昜 looks like a lizard basking under the sun 日 with its legs spread out. Together they form 蝪, a lizard.
For エキ, imagine a lizard basking on a rock, and you exclaim 'Eek!' when it suddenly darts away: 'Eek!' -> エキ.
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