Definition

1. Adverb:
   • Between noon and midnight: Used to specify that a time occurs in the afternoon or evening, after 12:00 noon and before 12:00 midnight.
2. Adjective:
   • After noon: Describing a time that falls within the period from noon until midnight.

Usage

• Adverb: The abbreviation "p.m." is placed after the numeral(s) indicating the hour to clarify that the time is in the afternoon or evening.
• Adjective: Used attributively before a noun (like "hours") to describe the time period.

Examples

• Adverb:
  • The store closes at 9 p.m.
  • The meeting is scheduled for 3:30 p.m.
• Adjective:
  • The p.m. hours are usually quieter in the office.
  • Please check the p.m. schedule.

Advanced Usage

• "12 p.m.": This specifically denotes noon, or midday (12:00 noon). It is the transition point from a.m. to p.m.
  • The deadline is at 12 p.m. sharp.
• Capitalization and Punctuation: While traditionally written with periods ("p.m."), it is increasingly common to see it written without them ("pm"). Both forms are acceptable in informal contexts, but "p.m." is standard in formal writing.
  • Formal: The ceremony begins at 6:00 p.m.
  • Informal: Let's meet at 8 pm.

Variants and Related Words

• Post meridiem: The full Latin phrase from which "p.m." is abbreviated. It means "after midday."
• a.m.: The counterpart abbreviation for times between midnight and noon (, meaning "before midday").
• Noon / Midday: 12:00 p.m.
• Midnight: 12:00 a.m.

Synonyms

• Afternoon/Evening/Night: These are general time period nouns, but they are not precise synonyms. "P.m." is a specific time indicator used with clock hours.
  • Compare: "We'll meet in the evening" vs. "We'll meet at 7 p.m."

Notes on Usage

• Clarity with "12": To avoid confusion between 12 a.m. (midnight) and 12 p.m. (noon), it is often clearer to use the words "noon" or "midnight."
  • Clear: The event starts at noon (not 12 p.m.).
  • Clear: The contract expires at midnight (not 12 a.m.).
• Use with O'clock: "P.m." can be used with "o'clock," though the numeral is typically spelled out.
  • The train departs at seven o'clock p.m.

Adverb

1. between noon and midnight
   • let's meet at 8 P.M.

Adjective

1. after noon