薄
ハク, うす.い, うす, うす, うす.める, うす.まる, うす.らぐ, うす.ら, うす.れる, すすき
dilute, thin, weak (tea)
JLPT2 G7 S16 F1009
As per 溥# (spread) + 艸 grass/plant → vegetation spread *thin* in shallow waters → *weak*; *light*; *pale*; *dim*; *shallow* → *dilute*; *fade* (← weaken).
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