HomeVocabulary ListsTop 100 Irregular Plural Nouns

Top 100 Irregular Plural Nouns

To improve your English grammar, we've compiled a list of 100 irregular plurals you should learn.

Siddharth Raayan
Siddharth RaayanImproving English


  • noun:addendum
  • plural noun:addenda

1)an item of additional material, typically omissions, added at the end of a book or other publication.

2)the radial distance from the pitch circle of a cogwheel, worm wheel, etc., to the crests of the teeth or ridges.


  • noun:aircraft
  • plural noun:aircraft

1)an airplane, helicopter, or other machine capable of flight.


  • noun:alumna
  • plural noun:alumnae

1)a female graduate or former student of a particular school, college, or university.

"the University of Ottawa alumna was in Japan"


  • noun:alumnus
  • plural noun:alumni

1)a graduate or former student, especially a male one, of a particular school, college, or university.

"a Harvard alumnus"


  • noun:analysis
  • plural noun:analyses

1)detailed examination of the elements or structure of something.

"statistical analysis"

2)short for psychoanalysis.

"other schools of analysis have evolved out of the original disciplines established by Freud"


  • noun:antenna
  • plural noun:antennae
  • plural noun:antennas

1)either of a pair of long, thin sensory appendages on the heads of insects, crustaceans, and some other arthropods.

"bugs use their antennae to detect blood heat"

2)a rod, wire, or other device used to transmit or receive radio or television signals.

"a TV antenna"


  • noun:antithesis
  • plural noun:antitheses

1)a person or thing that is the direct opposite of someone or something else.

"love is the antithesis of selfishness"


  • noun:apex
  • plural noun:apexes
  • plural noun:apices

1)the top or highest part of something, especially one forming a point.

"the living room extends right up into the apex of the roof"

  • noun:Apex

1)a system of reduced fares for scheduled airline flights and railroad journeys that must be booked and paid for before a certain period in advance of departure.

"Apex fares"


  • noun:appendix
  • plural noun:appendices
  • plural noun:appendixes

1)a tube-shaped sac attached to and opening into the lower end of the large intestine in humans and some other mammals.

"I'm merely standing in while Stella is having her appendix out"

2)a section or table of additional matter at the end of a book or document.

"a list of such activities was published as an appendix to the report"


  • noun:axis
  • plural noun:axes

1)an imaginary line about which a body rotates.

"the Earth revolves on its axis once every 24 hours"

2)a fixed reference line for the measurement of coordinates.

"the variable that is thought of as a cause is placed on the horizontal axis, and the variable that is thought of as an effect on the vertical axis"

  • noun:axis
  • plural noun:axis
  • noun:axis deer
  • plural noun:axis deer

1)a deer that has lyre-shaped antlers and a yellowish-brown coat with white spots, native to India and Sri Lanka.


  • noun:bacillus
  • plural noun:bacilli

1)a rod-shaped bacterium.


  • noun:bacterium
  • plural noun:bacteria

1)a member of a large group of unicellular microorganisms which have cell walls but lack organelles and an organized nucleus, including some that can cause disease.


  • plural noun:barracks
  • plural noun:barrack

1)a building or group of buildings used to house soldiers.

"the troops were ordered back to barracks"


  • noun:basis
  • plural noun:bases

1)the underlying support or foundation for an idea, argument, or process.

"trust is the only basis for a good working relationship"


  • noun:beau
  • plural noun:beaux
  • plural noun:beaus

1)a boyfriend or male admirer.

2)a rich, fashionable young man; a dandy.


  • noun:bison
  • plural noun:bison

1)a humpbacked shaggy-haired wild ox native to North America and Europe.


  • noun:bureau
  • plural noun:bureaux
  • plural noun:bureaus
  • noun:bur.

1)a chest of drawers.

2)an office or department for transacting particular business.

"a news bureau"


  • noun:cactus
  • plural noun:cacti
  • plural noun:cactuses

1)a succulent plant with a thick, fleshy stem that typically bears spines, lacks leaves, and has brilliantly colored flowers. Cacti are native to arid regions of the New World and are cultivated elsewhere, especially as houseplants.


  • noun:child
  • plural noun:children

1)a young human being below the age of puberty or below the legal age of majority.

"she'd been playing tennis since she was a child"


  • noun:chateau
  • plural noun:chateaux
  • plural noun:chateaus
  • noun:château
  • plural noun:châteaux

1)a large French country house or castle, often giving its name to wine made in its neighborhood.

"Château Margaux"

Showing 1 - 20 of 100 items
Showing 1 - 20 of 100 items