decay
verb uk/dɪˈkeɪ/ us/dɪˈkeɪ/
B2 [ I or T ]腐蚀;（使）衰败，（使）衰弱
to become gradually damaged, worse, or less; to cause something to do this
Sugar makes your teeth decay. 糖能引起蛀牙。
The role of the extended family has been decaying for some time. 大家庭的作用开始减弱已经有一段时间了。
Pollution has decayed the surface of the stonework on the front of the cathedral. 大教堂前部的石刻表面已经因为污染受到了侵蚀。
the smell of decaying meat 腐肉气味
[ I ] physics specialized（放射性物质）衰变
If a radioactive substance decays, it changes to a different form, producing radiation.
Radioactive uranium decays into stable lead at a known rate. 放射性铀以已知的速率衰变为稳定的铅。
As the actinium-225 decays, it gives off short-lived, highly energized alpha particles. 随着锕-225的衰变，它会释放出寿命短、能量高的α粒子。
- More examples
- Floating in the dirty river were dead fish, already starting to decay.
- The bacteria live on food particles and produce acid that decays the enamel on your teeth.
- The flesh on a dead body decays very rapidly.
- It's sad to watch a beautiful rose wither and decay in such a short time.
- Plants and animals decay into the soil, replenishing the minerals and nutrients.
decay
noun [ U ] uk/dɪˈkeɪ/ us/dɪˈkeɪ/
C2 腐蚀;衰败，衰弱
the process of decaying
environmental/industrial/moral/urban decay 环境恶化／工业衰退／道德沦丧／城市衰落
dental/tooth decay 蛀牙
The buildings had started to fall into decay. 那些建筑已经开始破败了。
This industry has been in decay for some time. 这个行业早就开始衰退了。
physics specialized（放射性物质的）衰变
the process by which a radioactive substance changes to a different form, producing radiation
Radon is emitted in the natural decay of radioactive materials in rock and soil. 氡是岩石和土壤中的放射性物质在自然衰变的过程中释放出来的。
the decay rate of beryllium-7 铍-7的衰变率
- More examples
- Many children come to us with severe dental decay.
- Unemployment and inner city decay are inseparable issues which must be tackled together.
- Sugar is a major cause of tooth decay.
- The mansion had an atmosphere of genteel elegance and decay.
- Areas of the most serious urban decay are to receive funds for new building and redevelopment schemes.