Editing Interlingua (section)

== Vocabulary ==
The maintainers of Interlingua select words for it based on their presence and commonality in languages dubbed 'control' languages.  These are [[Spanish language|Spanish]], [[Portuguese language|Portuguese]], [[Italian language|Italian]], [[French language|French]], and [[English language|English]], with [[German language|German]] and [[Russian language|Russian]] dubbed as secondary controls.  An Interlingua word's origin can be from any language so long as it has spread to the control languages.{{sfn|Morris|1945}}. Spanish and Portuguese, both [[West Iberian languages]], are treated as one unit. The largest number of Interlingua words are of [[Latin]] origin, with the [[Greek language|Greek]] and [[Germanic languages|Germanic]] languages providing the second and third largest number. The remainder of the vocabulary originates in [[Slavic languages]] and non-[[Indo-European languages]].{{sfn|Gode|1971|loc=Introduction}}

=== Eligibility ===

A word, that is a form with meaning, is eligible for the Interlingua vocabulary if it is verified by at least three of the four primary control languages. Either secondary control language can substitute for a primary language. Any word of Indo-European origin found in a control language can contribute to the eligibility of an international word.{{sfn|Stillman|Gode von Aesch|1943}} In some cases, the archaic or ''potential'' presence of a word can contribute to its eligibility.

A word can be potentially present in a language when a [[Morphological derivation|derivative]] is present, but the word itself is not. English ''proximity'', for example, gives support to Interlingua {{lang|ia|proxime}}, meaning 'near, close'. This counts as long as one or more control languages actually have this basic root word, which the Romance languages all do. Potentiality also occurs when a concept is represented as a [[compound (linguistics)|compound]] or derivative in a control language, the [[morpheme]]s that make it up are themselves international, and the combination adequately conveys the meaning of the larger word. An example is Italian {{lang|it|fiammifero}} (lit. 'flamebearer'), meaning 'match, lucifer', which leads to Interlingua {{lang|ia|flammifero}}, or 'match'. This word is thus said to be potentially present in the other languages although they may represent the meaning with a single morpheme.{{sfn|Gode|1971|loc=Introduction}}

Words do not enter the Interlingua vocabulary solely because [[cognate]]s exist in a sufficient number of languages. If [[semantic change|their meanings have become different over time]], they are considered different words for the purpose of Interlingua eligibility. If they still have one or more meanings in common, however, the word can enter Interlingua with this smaller set of meanings.{{sfn|Stillman|Gode von Aesch|1943}}

If this procedure did not produce an international word, the word for a concept was originally taken from Latin (see below). This only occurred with a few [[grammatical particle]]s.

=== Form ===
The form of an Interlingua word is considered an ''international prototype'' with respect to the other words. On the one hand, it should be neutral, free from characteristics peculiar to one language. On the other hand, it should maximally capture the characteristics common to all contributing languages. As a result, it can be transformed into any of the contributing variants using only these language-specific characteristics. If the word has any derivatives that occur in the source languages with appropriate parallel meanings, then their [[morphology (linguistics)|morphological]] connection must remain intact; for example, the Interlingua word for 'time' is spelled {{lang|ia|tempore}} and not {{lang|ia|*tempus}} or {{lang|ia|*tempo}} in order to match it with its derived adjectives, such as {{lang|ia|temporal}}.<ref>{{harvnb|Gode|1971|loc=Introduction}}. See [https://web.archive.org/web/20071227020831/http://www.bowks.net/worldlang/aux/b_IED-intro2.html#series "Forms of international words in derivational series"].</ref>

The language-specific characteristics are closely related to the [[sound law]]s of the individual languages; the resulting words are often close or even identical to the most recent form common to the contributing words. This sometimes corresponds with that of [[Vulgar Latin]]. At other times, it is much more recent or even contemporary. It is never older than the classical period.{{sfn|Stillman|Gode von Aesch|1943}}

=== An illustration ===
The French {{lang|fr|œil}}, Italian {{lang|it|occhio}}, Spanish {{lang|es|ojo}}, and Portuguese {{lang|pt|olho}} appear quite different, but they descend from a historical form {{lang|la|oculus}}. German {{lang|de|Auge}}, Dutch {{lang|nl|oog}} and English ''eye'' (cf. Czech and Polish {{lang|cs|oko}}, Russian and Ukrainian {{lang|ru|око}} ({{transliteration|ru|óko}})) are related to this form in that all three descend from [[Proto-Indo-European language|Proto-Indo-European]] ''{{PIE|*okʷ}}''. In addition, international derivatives like ''ocular'' and {{lang|it|oculista}} occur in all of Interlingua's control languages.{{sfn|Blandino|1989}} Each of these forms contributes to the eligibility of the Interlingua word.{{sfn|Stillman|Gode von Aesch|1943}} German and English base words do not influence the form of the Interlingua word, because their Indo-European connection is considered too remote.<ref>{{harvnb|Gode|1971|loc=Introduction}} See [https://web.archive.org/web/20071227020831/http://www.bowks.net/worldlang/aux/b_IED-intro2.html#method "Methods and techniques: Non-Latin examples"].</ref> Instead, the remaining base words and especially the derivatives determine the form {{lang|ia|oculo}} found in Interlingua.{{sfn|Blandino|1989}}

===Free word-building===
Words can also be included in Interlingua by deriving them using Interlingua words and [[affix]]es; a method called '''free word-building'''. Thus, in the [[Interlingua–English Dictionary]] (IED), [[Alexander Gode]] followed the principle that every word listed is accompanied by all of its clear compounds and derivatives, along with the word or words it is derived from. A reader skimming through the IED notices many entries followed by large groups of derived and compound words. A good example is the Interlingua word {{lang|ia|nation}}, which is followed by {{lang|ia|national}}, {{lang|ia|nationalismo}}, {{lang|ia|nationalista}}, {{lang|ia|nationalitate}}, {{lang|ia|nationalisar}}, {{lang|ia|international}}, {{lang|ia|internationalitate}}, and many other words.

Other words in the IED do not have derivatives listed. Gode saw these words as potential word families. Although all derived words in the IED are found in at least one control language, speakers may make free use of Interlingua roots and affixes. For example, {{lang|ia|jada}} ('jade') can be used to form {{lang|ia|jadificar}}, ('to jadify, make into jade, make look like jade'), {{lang|ia|jadification}}, and so on. These word forms would be impermissible in English but would be good Interlingua.

====Word-building by analogy====
Gode and Hugh E. Blair explained in the [[Interlingua: A Grammar of the International Language|Interlingua Grammar]] that the ''basic principle of practical word-building'' is analogical. If a pattern can be found in the existing international vocabulary, new words can be formed according to that pattern. A meaning of the suffix {{lang|ia|-ista}} is 'person who practices the art or science of....' This suffix allows the derivation of {{lang|ia|biologista}} from {{lang|ia|biologia}}, {{lang|ia|physicista}} from {{lang|ia|physica}}, and so on. An Interlingua speaker can freely form {{lang|ia|saxophonista}} from {{lang|ia|saxophone}} and {{lang|ia|radiographista}} from {{lang|ia|radiographia}} by following the same pattern.

====Usefulness and clarity====
As noted above, the only limits to free word-building in Interlingua are ''clarity'' and ''usefulness''. These concepts are touched upon here:

Any number of words could be formed by stringing roots and affixes together, but some would be more useful than others. For example, the English word ''rainer'' means 'a person who rains', but most people would be surprised that it is included in English dictionaries. The corresponding Interlingua word {{lang|ia|pluviator}} is unlikely to appear in a dictionary because of its lack of utility. Interlingua, like any traditional language, ''could'' build up large numbers of these words, but this would be undesirable.

Gode stressed the principle of ''clarity'' in free word-building. As Gode noted, the noun {{lang|ia|marinero}} ('mariner') can be formed from the adjective {{lang|ia|marin}}, because its meaning is clear. The noun {{lang|ia|marina}} meaning 'navy' cannot be formed, because its meaning would not be clear from the adjective and suffix that gave rise to it.