乙 = twist; second; second heavenly stem => in early text it means ‘fish entrails’ and may have been a pictographic representation; alternatively this character (radical 5) can be written 乛 , which is pronounced zheu3 (ㄓㄜ3), or 乚 , which is pronounced ia4 (lㄚ4) or in3 (lㄋ3) and in the latter case can be translated as ‘hidden, mysterious, secret; to conceal; small or minute’

related: 乛 , 乚

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