socks
襪 centers on foot coverings: socks or stockings. It is a specific clothing term for items worn on the feet.
襪 combines the clothing radical 衤 with 蔑, which likely provides the sound. The character specifically denotes socks or foot coverings.
The left side 衤 is clothing, and the right side 蔑 looks like a complex woven pattern. Picture a pair of socks with an intricate knit design.
For ベツ, imagine putting on your best socks before heading out: best -> ベツ, and your feet are snug in 襪.
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