a.

1. 特有的，独特的；典型的；表示特性的[（+of）]
   Urban inhabitants have to live with the characteristic noises of cities.

   城市居民不得不忍受都市特有的喧嚣。

   Quick decision is characteristic of him.

   快速决定是他的特征。

n.[C]

1. 特性，特征，特色
   It is their distinguishing characteristic.

   这是他们与众不同的特征。

2. 【数】（对数的）首数
   The characteristic of the logarithm 6.3214 is 6.

   对数6.3214的首数是6。

adj.

n.

1. a feature or quality typical of a person, place, or thing.
2. Mathematics  the whole number or integral part of a logarithm.