noun:

• around-the-clock system

noun:

• 24 divisions of the solar year; 24 terms used to denote the changing of the seasons

noun:

• 24 hours; twenty-four hours

noun:

• twenty-fourth day of the month
• twenty-four days

noun:

• Twenty-Four Histories; authoritative collection of twenty-four Chinese historical books ➜ 二十五史

noun:

• the 24 seasonal divisions of a year in the old lunar calendar - four character idiom