straw, one year
稘 centers on a period of time marked by a harvest cycle: one year, and by extension the straw associated with that cycle.
稘 combines 禾 (grain) with 其, which likely contributes the sound. The character is associated with a yearly harvest cycle, hence the meaning 'one year', and by extension 'straw'.
The grain plant 禾 beside 其 suggests a full cycle of planting and harvesting. Picture a year's worth of grain bundled as straw.
For キ, imagine a key that unlocks a barn full of straw after one year's harvest: key -> キ.
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