OpenSynonym

pa

/ˈpɑː/

NOUN

1. An informal term for father

An informal or affectionate term used to refer to or address one's father.

1.1. Family and affectionate address

Used in familiar or informal speech when talking about one's father or addressing him directly.

Synonyms

Examples

  • My pa taught me how to repair an old bicycle.
  • She visited her pa every weekend.
  • Pa sat on the porch and watched the sunset with his grandchildren.

Related Words

ADVERB

2. An abbreviation for per annum

An abbreviation for the Latin phrase per annum, meaning each year or every year, especially when describing interest rates, salaries, and other financial amounts.

2.1. Annual financial rates and payments

Used in financial and business contexts to indicate an amount calculated or paid on a yearly basis, commonly written as p.a.

Synonyms

  • per annum
  • per year
  • each year
  • annually
  • yearly

Examples

  • The account pays interest at a rate of five percent p.a.
  • The position offers a salary of $60,000 p.a.
  • The company charges an annual maintenance fee of $120 p.a.

Related Words

NOUN

3. A unit of pressure

The symbol Pa represents the pascal, the SI unit of pressure equal to one newton per square meter.

3.1. Scientific pressure measurement

Used in physics, engineering, and other technical fields to express pressure or mechanical stress.

Synonyms

  • pascal

Examples

  • The pressure sensor measures values in Pa.
  • The laboratory recorded a pressure difference of 500 Pa.

Related Words

  • pressure
  • force
  • area
  • newton
  • atmosphere
  • kilopascal

NOUN

4. The chemical element protactinium

Pa is the chemical symbol for protactinium, a radioactive metallic element with atomic number 91.

4.1. Chemistry and radioactive elements

Used as the standardized chemical symbol for protactinium in scientific writing, periodic tables, and nuclear chemistry.

Synonyms

  • protactinium
  • protoactinium

Examples

  • Pa is the chemical symbol for protactinium.
  • Researchers studied the radioactive properties of protactinium in the laboratory.

Related Words

  • chemical element
  • radioactivity
  • atomic number
  • uranium
  • actinium
  • periodic table

NOUN

5. An abbreviation for Pennsylvania

PA is the official two-letter postal abbreviation for the U.S. state of Pennsylvania.

5.1. Geographic and postal identification

Used in mailing addresses, location references, and other contexts where Pennsylvania is represented by its postal abbreviation.

Synonyms

  • Pennsylvania
  • Keystone State

Examples

  • The package was shipped to Harrisburg, PA.
  • She moved to Pennsylvania and updated her mailing address.

Related Words

  • Philadelphia
  • Pittsburgh
  • United States
  • state abbreviation
  • postal address

NOUN

6. A public address system

An abbreviation for public address, referring to an electronic sound amplification system used to broadcast speech or other audio to an audience.

6.1. Sound amplification and public announcements

Used to refer to equipment that amplifies voices or audio for distribution throughout a public or shared space.

Synonyms

  • public address system
  • PA system
  • P.A. system
  • loudspeaker system
  • speaker system
  • amplification system

Examples

  • The announcer spoke through the PA system.
  • The school installed a new public address system for emergency announcements.
  • The concert organizers tested the speakers before opening the venue.

Related Words

  • microphone
  • loudspeaker
  • amplifier
  • audio equipment
  • announcement
  • sound reinforcement