marinate, pickle, salt
醃 centers on preserving food by soaking it in a salty or acidic liquid: marinating, pickling, or salting.
醃 combines 酉 (a jar for alcohol or fermentation) with 奄, which likely contributes the sound. Together they suggest preserving food in a jar with salt or brine.
The left side 酉 is a jar used for brewing or pickling, and the right side 奄 looks like a lid covering something inside. Picture a jar filled with vegetables being salted and sealed to pickle.
For エン, imagine an English pub where they serve pickled eggs in a jar: the 'en' in English cues エン, and the jar 酉 holds the pickled food.
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