Time is referred to as follows:
23:00~00:59 is called Zi Shi (子时).
01:00~02:59 is called Chou Shi (丑时).
03:00~04:59 is called Yin Shi (寅时)
05:00~06:59 is called Mao Shi (卯时)
07:00~08:59 is called Chen Shi (辰时)
09:00~10:59 is called Si Shi (巳时)
11:00~12:59 is called Wu Shi (午时)
13:00~14:59 is called Wei Shi (未时)
15:00~16:59 is called Shen Shi (申时)
17:00~18:59 is called You shi (酉时)
19:00~20:59 is called Xu Shi (戌时)
21:00~22:59 is called Hai Shi (亥时)
With the shi (时) means hour.
There is also another set which describes the time of the night which is:
19:00~20:59 is called Yi Geng(一更)
21:00~22:59 is called Er Geng(二更)
23:00~00:59 is called San Geng(三更)
01:00~02:59 is called Si Geng(四更)
03:00~04:59 is called Wu Geng(五更)
The second one can be translated as the First Night’s Watch, Second, Third and so on.