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to spill; to fall out of; to overflow
to peek through; to become visible (although normally not)
to escape (of a smile, tear, etc.)
コップから水がこぼれましたよ。
Water spilled from the cup.
涙がこぼれそうになりました。
Tears were about to spill.
米がこぼれないように運んで。
Carry so rice doesn't spill.