decay

腐敗、虫歯

歯、木、食べ物などの有機物が自然に傷んで分解されること。

やさしい英語で： The natural breakdown of teeth, wood, food, or other living material.

• Sugar can cause tooth decay.
• Moisture encouraged decay in the wooden fence.
• Fungi speed up the decay of fallen leaves.

類義語： rot, rotting, decomposition

よく使う表現： tooth decay, dental decay, wood decay

崩壊、減衰

物が徐々に崩れたり、強さや量が減ったりすること。

やさしい英語で： The gradual process of breaking down or becoming less strong or less in amount.

• The decay happened slowly.
• The graph shows the rate of decay.
• Heat can speed up the decay of some materials.

使い方： decay of something (We measured the decay of the signal over time.)

類義語： breakdown, decline

よく使う表現： gradual decay, rate of decay, exponential decay

衰退、荒廃

強さ、質、成功、よい状態が徐々に失われること。

やさしい英語で： A gradual loss of strength, quality, success, or good condition.

• The city showed signs of decay.
• Years of neglect led to the decay of the building.
• She blamed corruption for the moral decay of society.

使い方： decay of something (The report describes the decay of public services.); fall into decay (The empty houses fell into decay.)

類義語： decline, deterioration

反対語： renewal

よく使う表現： urban decay, moral decay, fall into decay

腐敗物、虫歯

腐って傷み、柔らかくなった物や、虫歯で傷んだ部分。

やさしい英語で： Material that has become damaged and soft through rotting.

• The dentist removed the decay.
• Dark decay filled the hole in the tooth.
• They scraped the soft decay out of the old beam.

類義語： rot

よく使う表現： remove decay, wood decay, full of decay

腐る、腐敗する

自然に分解され、傷んだり柔らかくなったりする。

やさしい英語で： To break down naturally, becoming damaged, soft, or rotten.

• The fallen fruit began to decay.
• Damp wood decays quickly.
• The leaves had decayed by spring.

類義語： rot, decompose

よく使う表現： decay slowly, begin to decay, decay in soil

衰退する、老朽化する

徐々に弱くなったり、状態が悪くなったりする。

やさしい英語で： To gradually become weaker or worse in condition.

• The empire began to decay.
• Public institutions decayed under weak leadership.
• The abandoned buildings are decaying rapidly.

類義語： deteriorate, decline

反対語： improve

よく使う表現： decay over time, begin to decay, decay gradually

減衰する、薄れる

徐々に目立たなくなったり、消えたりする。

やさしい英語で： To slowly become less noticeable or disappear.

• The sound slowly decayed.
• The signal decays as it travels farther.
• The vibration had decayed before we took another reading.

類義語： fade, diminish

反対語： intensify

よく使う表現： decay away, decay with time, decay rapidly

腐らせる、劣化させる

物を腐らせたり、徐々に傷ませたりする。

やさしい英語で： To make something rot or gradually become damaged.

• Dampness decayed the floorboards.
• Acids can decay teeth over time.
• Years of rain had decayed the exposed beams.

使い方： decay something (Constant moisture decayed the wooden supports.)

類義語： rot, damage

反対語： preserve

よく使う表現： decay something, decay the wood