Dating abbreviations meanings
As with other abbreviations, spell out the name of the group upon first mention in the text and then provide the abbreviation.If the name of the group first appears in the narrative, put the abbreviation, a comma, and the year for the citation in parentheses after it.Imagine being asked to pick up a friend at the airport at am on April 13.
Ante meridiem is commonly denoted as AM, am, a.m., or A.
Starting at midnight, hours are numbered from 0 to 24, removing the need for designations like am and pm.
For example, at , 23 hours have passed since the beginning of the current day.
M.; post meridiem is usually abbreviated PM, pm, p.m., or P. Like many other sources, uses am and pm, but the other variants are equally correct and widely used. The main weakness of the 12-hour system is a widespread confusion about which abbreviation should be used for noon and midnight: neither moment can logically be identified as before noon (am) or after noon (pm).
For example, the moment of midnight occurs precisely 12 hours after noon on the previous day and 12 hours before noon on the following day.