This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
啘 combines 口 (mouth) with 宛, which likely contributes the sound. The exact historical development is uncertain.
With 口 (mouth) on the left, 啘 might relate to speech or sound, but its meaning is unclear. Picture a mouth making an uncertain sound.
For エン, imagine the mouth 口 making an 'en' sound, like the start of 'end' but cut short: en -> エン.
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