The studies by Werner Betz (1949, 1959), Einar Haugen (1950, also 1956), and Uriel Weinreich (1953) are regarded as the classical theoretical works on loan influence. The basic theoretical statements all depart from Betz’s nomenclature. Duckworth (1977) enlarges Betz’s scheme by the type “partial substitution” and supplements the system with English terms:
On the basis of an importation-substitution distinction, Haugen (1950: 214f.) distinguishes three basic groups of borrowings: “(1) Loanwords show morphemic importation without substitution. [. . .]. (2) Loanblends show morphemic substitution as well as importation. [. . .]. (3) Loanshifts show morphemic substitution without importation”. Haugen has later refined (1956) his model in a review of Gneuss’s (1955) book on Old English loan coinages, whose classification, in turn, is the one by Betz (1949) again.
Weinreich (1953: 47ff.) differentiates between two mechanisms of lexical interference, namely those initiated by simple words and those initiated by compound words and phrases. Weinreich (1953: 47) defines simple words “from the point of view of the bilinguals who perform the transfer, rather than that of the descriptive linguist. Accordingly, the category ‘simple’ words also includes compounds that are transferred in unanalysed form”. After this general classification, Weinreich then resorts to Betz’s (1949) terminology.
Ghil'ad Zuckermann's analysis of multisourced neologization (2003) challenges Einar Haugen's classic typology of lexical borrowing . While Haugen categorizes borrowing into either substitution or importation, Zuckermann explores cases of "simultaneous substitution and importation" in the form of camouflaged borrowing. He proposes a new classification of multisourced neologisms, words deriving from two or more sources at the same time. Examples of such mechanisms are phonetic matching, semanticized phonetic matching and phono-semantic matching. Phono-semantic matching is distinct from calquing. While calquing includes (semantic) translation, it does not consist of phonetic matching (i.e. retaining the approximate sound of the borrowed word through matching it with a similar-sounding pre-existent word/morpheme in the target language).
English has many loanwords. In 1973, a computerised survey of about 80,000 words in the old Shorter Oxford Dictionary (3rd edition) was published in Ordered Profusion by Thomas Finkenstaedt and Dieter Wolff. Their estimates for the origin of English words were as follows:
However, if the frequency of use of words is considered, words from Old and Middle English occupy the vast majority.
The reasons for English's vast borrowing include:
This lack of restrictions makes it comparatively easy for the English language to incorporate new words. However, the English pronunciations of loanwords often differ from the original pronunciations to such a degree that a native speaker of the language it was borrowed from is not able to recognize it as a loanword when spoken.
English has often borrowed words from the cultures and languages of the British Colonies. For example, words borrowed from Hindi include syce/sais, dinghy, chutney, pundit, wallah, pajama/pyjamas, bungalow and jodhpur. Other examples include trek, aardvark, laager, wildebeest and veld from Afrikaans, shirang, amok (Malay) and sjambok (Malay via Afrikaans).
English also acquires loanwords in which foreign sounds are part of the foreign pronunciation. For example, the Hawaiian word aā is used by geologists to specify lava that is relatively thick, chunky, and rough. The Hawaiian spelling indicates the two glottal stops in the word, but the usual English pronunciation, [ˈɑ.ɑ], does not contain the glottal stop. In addition, the English spelling usually removes the okina and macron diacritic.
During the Ottoman period, Turkish literature became heavily influenced by Persian and Arabic borrowings. During more than 600 years of the Ottoman Empire, the literary and official language of the empire was a mixture of Turkish, Persian, and Arabic, which is now called Ottoman Turkish, considerably differing from the everyday spoken Turkish of the time. Many Turkish, Persian and Arabic words were also loaned to other languages of the empire, such as Bulgarian and Serbian. After the empire fell in World War I and the Republic of Turkey was founded, the Turkish language underwent an extensive language reform led by the newly founded Turkish Language Association, during which many loanwords were replaced with equivalent words derived from Turkic roots. The language reform was a part of the ongoing cultural reform of the time, in turn a part in the broader framework of Atatürk's Reforms, and included the introduction of the new Turkish alphabet. Turkish also has many loanwords derived from French, such as pantalon for 'trousers' and komik for 'funny' (from Fr. comique), all of them pronounced very similarly (except for the French pronunciation of the letter 'r').
The Italian government has recently expressed its displeasure over the borrowing of English words and syntax in Italian. English words are often used where they are more convenient than a longer Italian expression, as in "computer" for elaboratore elettronico or "week-end" for finesettimana; but also where equally convenient Italian words already exist, as in "fashion" for moda and "meeting" for conferenza.
Words are occasionally borrowed with a different meaning than the meaning in the source language. Among the most well-known examples of this is the German word Handy, which is a borrowing of the English adjective handy, but means mobile phone and is thus a noun. Conversely, in English the prefix über-, taken from German, is used in a way that it is rarely used in German.
Words borrowed into different languages are sometimes spelled as in the original language (such as many of the loanwords above). Sometimes loanwords retain original (or near-original) pronunciation, but undergo a spelling change to represent the orthography of the adopting language. Welsh is a language where this is done with some consistency, with words like gêm (game), cwl (cool), and ded-gifawe (dead giveaway).
Some languages, such as Jèrriais, have a tendency to apply historical sound-shift patterns to new borrowed words; while Jèrriais speakers would have little difficulty pronouncing "parki", partchi (to park) is the word used, displaying the typical Norman ki->tchi shift.
Most languages modify loanwords to fit native pronunciation patterns. An excellent example of this is Japanese. Japanese contains a tremendous amount of loanwords (gairaigo). Ignoring ancient influence from China, recently most Gairaigo has come from English, though there have been significant borrowings from Dutch, German and other languages. There are almost always significant pronunciation shifts (baseball -> beisubaru). Longer terms often are shortened (word processor -> wapuro). In some cases the original meaning shifts considerably through unexpected logical leaps (smorgasboard -> baikingu (Viking): the word smorgasboard is of Norse origin). In other cases the words are borrowed and used in totally inexplicable contexts, with words picked seemingly at random. This is often the case in the names of small businesses, or in artistic works as seen in many anime and manga series such as Bubblegum Crisis. Gairaigo is such a large part of the modern Japanese vocabulary that there are specialized dictionaries for it.
Another example of this is found in Northern Africa where the Spanish word "Zapato" is used for the word shoe. However, the word "Zapato" came from the Arabic word for shoe: "Sabbat" (سباط) which was borrowed by the Spanish when the Islamic Arabs were living in Andalusia (modern day Spain).