Civil day Meaning, Definition & Usage
- 
       noun a day reckoned from midnight to midnight
       
       
 calendar day.
 
WordNet
Definitions
- the mean solar day, used in the ordinary reckoning of time, and among most modern nations beginning at mean midnight; its hours are usually numbered in two series, each from 1 to 12. This is the period recognized by courts as constituting a day. The Babylonians and Hindoos began their day at sunrise, the Athenians and Jews at sunset, the ancient Egyptians and Romans at midnight.