Novial^{[lower-alpha 1]} is a constructed international auxiliary language (IAL) for universal human communication between speakers of different native languages. It was devised by Otto Jespersen, a Danish linguist who had been involved in the Ido movement that evolved from Esperanto at the beginning of the 20th century, and participated later in the development of Interlingua. The name means 'new' + 'international auxiliary language'.

Its vocabulary is based largely on the Germanic and Romance languages while its grammar is influenced by English.

Novial was introduced in Jespersen's book An International Language in 1928.^[1] It was updated in his dictionary Novial Lexike in 1930,^[2] and further modifications were proposed in the 1930s, but the language became dormant with Jespersen's death in 1943.^[3] In the 1990s, with the revival of interest in constructed languages brought on by the Internet, some people rediscovered Novial.^{[citation needed]}

The digraphs ch and sh represent [t͡ʃ] or [ʃ], depending on the speaker. For example, chokolate would be pronounced either /t͡ʃokoˈlate/ or /ʃokoˈlate/.^[1]

Like many constructed IALs, Novial has a simple and regular grammar. The main word order is SVO, which removes the need for marking the object of a sentence with accusative case (since the position normally tells what word is the object). There is however a way to mark accusative. There is no grammatical gender (but the sex or gender of referrents can be marked). Verbs are conjugated without agreement (according to person or number), and have a regular conjugation.

Nouns mainly end in e, a, o, u or um in singular. There is definite forms of nouns marked with an article, and singular and plural forms, where plural is marked with the suffix -s after vowels or -es after consonants. There is also a form for indefinite number (like in Mandarin Chinese and Japanese, for example), expressed by removing the ending of the noun in singular (leone – lion, leon es kruel – 'a/the lion is cruel', or 'lions are cruel').^[5]

If a noun refers to a living being, then the form ending in -e is neutral in regards to sex, the one ending in -a female, and the one ending in -o male. If the noun is based on an adjective, nouns referring to living beings can be made with the previously mentioned rule, and furthermore nouns referring to concrete objects with -u, and abstractions with -um. The third person pronouns follows the same rule, together with the definite article.

In the case of a noun that refers to an instrument – a tool or a means – the word that ends in -e is the tool or the means itself, -a the verb describing usage of the tool and so on, and -o the noun describing the act^[6] of that using:

Jespersen was a professional linguist, unlike Esperanto's creator.^{[neutrality is disputed]} He disliked the arbitrary and artificial character that he found in Esperanto and Ido.^[8] Additionally, he objected to those languages' inflectional systems, which he found needlessly complex. He sought to make Novial at once euphonious and regular while also preserving useful structures from natural languages.

In Novial:

• Syntax is largely a matter of word order, as in English and modern Scandinavian languages. There is no obligatory accusative marker as in Esperanto, but the accusative may optionally be marked with either an accusative ending or an accusative preposition.
• A genitive or possessive case is available as an alternative to the preposition de. This is based on Jespersen's observation that many modern languages have lost complex noun inflections, yet retain a possessive form.
• Auxiliary particles express most verb tenses. An inflectional ending is available as a shorthand for the simple past tense.

A major difference between Novial and Esperanto/Ido concerns noun endings. Jespersen rejected a single vowel to terminate all nouns (-o in Esperanto/Ido), finding it unnatural and potentially confusing. ^[9] Instead, Novial nouns may end in -o, -a, -e, or -u or -um. These endings may be taken to indicate natural sex according to the custom in Romance languages, though there is no grammatical gender or requirement for adjectives to agree with nouns.

Here is the Lord's Prayer in Novial and several related languages:

As Jespersen relates in his autobiography, in 1934 he proposed an orthographic reform to Novial, which displeased a part of the users. Jespersen abandoned the essential principle of one sound, one letter :^[10]

I proposed some not inconsiderable amendments, especially by introducing an "orthographic" Novial alongside the original phonetically written language. (...) Thus the sound [k], besides being represented by the letters k and q and the first part of x, also acquired the new sign c (before a, o, u and consonants), a practice with which nearly all Europeans, Americans, and Australians are familiar from childhood. (...) I know that this orthographic form has displeased several of Novial's old and faithful friends, but it is my impression that many others have applauded it.

— Otto Jespersen (1995 [1938], pp. 227–8)

Some of Jespersen's colleagues among philologists jokingly referred to Novial as Jesperanto, combining his surname with Esperanto, the prototypical auxiliary language.

• Comparison between Esperanto and Novial
• Comparison between Ido and Novial