涌
ユウ, ヨウ, ユ, わ.く

boil, ferment, seethe, uproar, breed

JLPT0 G13 S0 F5000

As per 甬# (run through) + 水 water → gushing water running through a hole and up to the surface of the earth (compare 湧) → *gush forth/out*; *spring up* (naturally); *breed*.

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