預
ヨ, あず.ける, あず.かる
deposit, custody, leave with, entrust to
JLPT2 G5 S13 F981
予# (stretch) + 頁 people → long line of reserve troops, or other personnel → *in advance* (← keep/prepare in advance) → *keep* → *deposit* → *entrust* (← entrust funds for safekeeping).
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