湧
ユウ, ヨウ, ユ, わ.く, わき, わく

boil, ferment, seethe, uproar, breed

JLPT1 G7 S12 F2070

As per 勇# (run through) + 水 water → water that runs through an aperture in gushing from the earth (compare 涌) → *gush forth/out*; *spring up* (naturally); *breed*.

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