Trumpian  tweet, a Shakespearean  play, the Thai baht, French cars

Each of the four examples above contains an adjective ( Trumpian, Shakespearean, Thai, French) and you will immediately note that each adjective is capitalized—it starts with a capital letter. That is because each of those adjectives comes from a name (Trump, Shakespeare, Thailand, France). Names of people, organizations, countries, towns etc are "proper nouns" and need to be capitalized in English. Adjectives made from proper nouns are "proper adjectives" and also need to be capitalized.

Proper nouns are nouns that refer to unique places, people or organizations. The word "country" is a common noun because there are many countries. The word "Thailand" is a proper noun because there is only one Thailand and Thailand is its name. Just like you. You are unique and you have a name. Your name is a proper noun and in English we spell it with a capital letter at the start (example Elizabeth, Donald).

What are Proper Adjectives?

Most adjectives are "common adjectives". They describe people, places and things, for example:

  • tall man, big dog, noisy baby
  • large garden, empty room, beautiful city
  • red car, hot weather, expensive watch

" Proper adjectives" also describe people, places and things, but they are based on names  and therefore need to be capitalized, like the names. For example, Spain is the name of a country and starts with a capital letter. The adjective based on Spain (Spanish) must also start with a capital letter. Mars is the name of a planet and starts with a capital letter. The adjective based on Mars (Martian) must also start with a capital letter. Shakespeare was the name of a famous writer and starts with a capital letter. The adjective based on Shakespeare (Shakespearean) must also start with a capital letter.

  • Since you live in Spain, do you enjoy Spanish food?
  • If people ever live on the planet Mars, they will have to endure the extremes of the Martian climate.
  • Although William Shakespeare is best known for his plays, many exams also cover Shakespearean poetry.

Proper adjectives are mostly of two types:

  1. those that come from names of places—countries, continents, regions, cities
  2. those that come from names of people—usually famous people, mostly historical, some modern

Proper Adjectives from Place Names (countries, continents, regions, cities)

Your country is a proper noun and it has a capitalized proper adjective. Here are a few examples of proper adjectives based on place names

(place name)
proper noun
proper adjectiveexample sentence
AfricaAfricanJumbo was a famous African elephant.
AlaskaAlaskanI just love to eat Alaskan salmon.
AlpsAlpineWe need an Alpine guide, please.
AmazonAmazonianThey cut their way through the Amazonian rainforest.
AntarcticaAntarcticNothing could prepare them for the ferocity of the Antarctic winds.
AsiaAsianHow many Asian countries have you visited?
Atlantis (fictional)AtlanteanHe built an Atlantean castle for himself.
BaliBalineseThey scanned the Balinese skyline.
BarcelonaBarcelonianThis is one of many Barcelonian traditions.
BrazilBrazilianI have a Brazilian boss.
BritainBritishMy teacher is British.
ChinaChineseLet's go to a Chinese restaurant.
Costa RicaC osta RicanWhat are the Costa Rican beaches like?
HimalayasHimalayanHave you ever experienced a Himalayan winter?
IranIranianWe haven't crossed the Iranian border yet.
LaosLaotianIs there a Laotian consulate here?
Lilliput (fictional)LilliputianThe only way this Lilliputian economy can grow is by exporting.
MadagasacarMadagascan,
Malagasy
His wife is Malagasy.
MexicoMexicanDo you like Mexican food?
Middle EastMiddle EasternThere has been a massive growth in Middle Eastern airlines.
MoscowMuscoviteHe was accompanied by two Mucovite women.
ParisParisianMany Parisian streets are lined with trees.
PolynesiaPolynesianIt is one of the most endearing Polynesian traditions.
South AmericaSouth AmericanCape Horn is the southern tip of the South American landmass.
the PhilippinesPhilippineCan you change some Philippine pesos?
TibetTibetanHe photographed the stunning Tibetan landscapes.
TorontoTorontonianWe inched our way through the Torontonian traffic.
UzbekistanUzbekThe Uzbek border is five miles from here.
ViennaVienneseThough I was born in London, my father was Viennese.

Proper Adjectives from People's Names (eponymous )

Your name is a proper noun and if you were super-famous it might have a capitalized proper adjective. Nouns and adjectives derived from people's names—both real and fictional—are called "eponymous". Eponymous adjectives are by definition proper adjectives. Here are a few examples

(person's name)
proper noun
proper adjectiveexample sentence
Gautama BuddhaBuddhistThis is the most famous of the Buddhist temples here.
ConfuciusConfuciawasHe was a famous Confucian scholar.
Charles DarwinDarwinianSome people challenge the concept of Darwinian evolution.
Jesus ChristChristianThese traditions are inherently Christian.
Queen ElizabethElizabethanPart of this building is Elizabethan.
Adolf HitlerHitlerianThe Hitlerian moustache originated in the need to trim moustaches to fit under gas-masks, worn in response to British mustard gas attacks.
Niccolò MachiavelliMachiavellianThe tactics he encountered were almost Machiavellian.
Karl MarxMarxistWe discussed the finer points of Marxist theory.
George OrwellOrwellianThe vision he described was of a truly Orwellian future.
Vladimir PutinPutinistMany believe that the Putinist doctrine is no more than old-fashioned nationalism.
William ShakespeareShakespeareanHow many Shakespearean plays have been made into films?
Margaret ThatcherThatcheriteHe was at best a devoted Thatcherite editor.

Prefixes with Proper Adjectives

Normally, a prefix attached to a proper adjective should not be capitalized. Look at these examples:

  • pre-Christian
    Paganism was one of many pre-Christian religions.
  • pan-European
    The search for a pan-European identity started well before 1900.
  • post-Thatcherite
    Did wages go up in post-Thatcherite Britain?

Note that the prefix should not be capitalized, unless it starts the sentence:

  • anti-Western
    Anti-Western sentiment was an inevitable consequence.

If the prefix itself is formed from a proper noun, then the prefix should of course by capitalized. In the following example, Austro-  comes from the proper noun Austria and Hungarian  comes from the proper noun Hungary.

  • Austro-Hungarian
    The assassination of the heir to the Austro-Hungarian throne led directly to the First World War.

In the next example, the prefix Afro-  comes from the proper noun Africa, and Caribbean  is the proper adjective from the proper noun Caribbean:

  • Afro-Caribbean
    He loves Afro-Caribbean music.

Hyphenation with Proper Adjectives

The same logic applies with suffixes and other hyphenated forms—capitalize only the word or words derived from a proper noun:

  • English-speaking
    She asked for an English-speaking guide to show her around.

When Proper Adjectives Lose their Connection

Sometimes proper adjectives lose their connection with the proper noun that gave them the right to be capitalized, for example:

  • gargantuan, titanic, caesarian, draconian, herculean, spartan

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