名詞 extinction:

1. no longer in existence
   同義詞：defunctness
2. no longer active; extinguished
3. the reduction of the intensity of radiation as a consequence of absorption and radiation
4. complete annihilation
   同義詞：extermination
5. a conditioning process in which the reinforcer is removed and a conditioned response becomes independent of the conditioned stimulus
   同義詞：experimental extinction
6. the act of extinguishing; causing to stop burning
   同義詞：extinguishing, quenching

1. The race was threatened with extinction.
   這個種族這時眼看要滅絕了。
2. His movie of the extinction of dinosaurs was a great success.
   他的關(guān)于恐龍滅絕的電影取得了巨大的成功。
3. Is the human race threatened with complete extinction?
   人類是否會受到完全滅絕的威脅呢？

ex.tinc.tion

n.（名詞）

The act of extinguishing.
滅絕：滅絕的行為
The condition of being extinguished.
被滅絕的條件
The fact of being extinct or the process of becoming extinct:
滅絕：滅絕的事實或變絕種的經(jīng)過：
例句：
.The most effective agent in the extinction of species is the pressure of other species.(Alfred R. Wallace)
.在種的滅絕中最有影響的力量是其它種的壓力.(艾爾弗雷德R.華萊士)

Psychology A reduction or a loss in the strength or rate of a conditioned response when the unconditioned stimulus or reinforcement is withheld.
【心理學(xué)】 條件反射減弱：當(dāng)非條件的刺激或強(qiáng)化停止時，條件反應(yīng)的速度或力度的減少或喪失
Physiology A gradual decrease in the excitability of a nerve to a previously adequate stimulus, usually resulting in total loss of excitability.
【生理學(xué)】 衰竭：神經(jīng)對足夠的刺激所產(chǎn)生的興奮的逐漸減少，常導(dǎo)致興奮的完全喪失