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to well (up); to gush out (of water); to spring out; to surge
to appear (esp. suddenly) (sweat, tears, etc.); to sweat; to cry
to feel emotions (e.g. joy, bravery, etc.); to spring up (e.g. an idea, emotions, clouds); to well up; to arise
to hatch; to breed; to propagate; to be infested (esp. of parasitic insects, etc.)
温泉からお湯が勢いよく湧いている。
Hot water is gushing vigorously.
山の先に天然の温泉が湧き出ている。
Hot springs are welling up.
応援のおかげで勇気が湧いてきた。
Courage welled up in me.