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to be worm-eaten; to be eaten by worms
to affect adversely; to spoil; to ruin; to undermine; to gnaw at (one's heart, body, etc.); to eat into; to destroy
白蟻が古い柱を蝕んだ。
Termites ate away at the old wooden pillar.
汚職が国民の信頼を蝕んでいる。
Corruption is eroding public trust.
過度なストレスは徐々に健康を蝕みます。
Excessive stress gradually erodes one's health.