Hello, you have come here looking for the meaning of the word p.m.. In DICTIOUS you will not only get to know all the dictionary meanings for the word p.m., but we will also tell you about its etymology, its characteristics and you will know how to say p.m. in singular and plural. Everything you need to know about the word p.m. you have here. The definition of the word p.m. will help you to be more precise and correct when speaking or writing your texts. Knowing the definition ofp.m., as well as those of other words, enriches your vocabulary and provides you with more and better linguistic resources.
We never say 12 a.m. or 12 p.m. It's either 12 midnight or 12 noon, respectively.
2009, Robert Bill, Medical Mathematics and Dosage Calculations for Veterinary Professionals, page 348:
The 12-hour clock uses A.M. for the morning hours of midnight (12:00 A.M.) to almost noon (11:59 A.M.) and the P.M. designation for the hours from noon (12:00 P.M.) to almost midnight (11:59 PM).
2015, Arhlene A. Flowers, Global Writing for Public Relations, page 141:
The 12-hour clock, which is used in the U.S., Canada, and a few other countries, divides time into two cycles: a.m. (ante meridiem, Latin for before midday) from midnight, 12 a.m., to 11:59 a.m.; and p.m. (post meridiem, Latin for after midday) from noon, 12 p.m., to 11:59 p.m.
2023 August 3, Yeh Chen, Bernadette Hsiao, “4 found without vital signs after vehicle plunges into rural Taoyuan valley”, in Focus Taiwan, archived from the original on 03 August 2023, Society:
The Taoyuan City Fire Department said that two others, a man and a woman, were pulled from the vehicle alive after rescuers were called to the scene of the accident near Sbunaw Bridge in Fuxing District at 12:27 p.m.
Usage notes
As seen in the quotes above, "12 p.m." has sometimes been used to mean either noon or midnight. However, the National Institute of Standards and Technology contends that those uses are incorrect.
Some argue that it should not be used in English as a noun meaning "afternoon" on account of the fact that it is an abbreviation for a Latin adverbial phrase.