Untranslatability is the property of text or speech for which no equivalent can be found when translated into another (given) language. A text that is considered to be untranslatable is called a lacuna, or lexical gap. The term arises when describing the difficulty of achieving the so-called perfect translation. It is based on the notion that there are certain concepts and words that are so interrelated that an accurate translation becomes an impossible task.

Some writers have suggested that language carries sacred notions or is intrinsic to national identity. Brian James Baer posits that untranslatability is sometimes seen by nations as proof of the national genius. He quotes Alexandra Jaffe: "When translators talk about untranslatable, they often reinforce the notion that each language has its own 'genius', an 'essence' that naturally sets it apart from all other languages and reflects something of the 'soul' of its culture or people".

A translator, however, can resort to various translation procedures to compensate for a lexical gap. From this perspective, untranslatability does not carry deep linguistic relativity implications. Meaning can virtually always be translated, if not always with technical accuracy.

Theories There is a school of thought identified with Walter Benjamin that identifies the concept of "sacred" in relation to translation, and this pertains to the text that is untranslatable because its meaning and letter cannot be disassociated. It stems from the view that translation should realize the imagined perfect relationship with the original text. This theory highlights the paradoxical nature of translation wherein it—as a process—assumes the forms of necessity and impossibility at the same time. This is demonstrated in Jacques Derrida's analysis of the myth of Babel, a word which he described as a name that means confusion and also a proper name of God. Furthermore, Derrida noted that when God condemned the world to a multiplicity of tongues, he created a paradoxical need and impossibility of translation.

Derrida himself put forward his own notion of the untranslatability of the text, arguing in his early works such as the Writing and Difference and Margins of Philosophy that there is an excess of untranslatable meaning in literature, and it cannot be reduced to a closed system or a restricted economy "in which there is nothing that cannot be made to make sense."

Brian James Baer posits that untranslatability is sometimes seen by nations as proof of their national genius. Literature that can be easily translated may be considered as lacking originality, while translated works themselves may be regarded merely as imitations. Baer quotes Jean-Jacques Rousseau defining true genius as "the kind that creates and makes everything out of nothing". Paraphrasing Robert Frost's remark about poetry ("Poetry is what gets lost in translation"), Baer suggests that "one could define national identity as that which is lost in translation". He further quotes Alexandra Jaffe: "When translators talk about untranslatable, they often reinforce the notion that each language has its own 'genius', an 'essence' that naturally sets it apart from all other languages and reflects something of the 'soul' of its culture or people".

Quite often, a text or utterance that is considered to be "untranslatable" is called a lacuna, or lexical gap. That is, there is no one-to-one equivalence between the word, expression or turn of phrase in the source language and another word, expression or turn of phrase in the target language. A translator can, however, resort to a number of translation procedures to compensate for this. From this perspective, untranslatability or difficulty of translation does not always carry deep linguistic relativity implications; denotation can virtually always be translated, given enough circumlocution, although connotation may be ineffable or inefficient to convey.

Examples

Register Although Thai has words that can be used as equivalent to English "I", "you", or "he/she/it", they are relatively formal terms (or markedly informal). In most cases, Thai people use words which express the relation between speaker and listener according to their respective roles. For instance, for a mother to say to her child "I'll tell you a story", she would say "" (), or "Mother will tell child a story". Similarly, older and younger friends will often use sibling terminology, so that an older friend telling a younger friend "You're my friend" would be "" (), would translate directly as "Younger sibling is older sibling’s friend". To be translated into English correctly, it is proper to use "I" and "you" for these example statements, but normal Thai perceptions of relation are lost in the process.

A similar feature can also be observed in Indonesian. One may use the formal form of pronouns, which are generally distinct from the informal/familiar forms; however, the use of these pronouns does not evoke sufficient friendliness or intimacy, especially in spoken language. Instead of saying "", a waiter/waitress will most likely say "" (lit. 'Father/Mother wants to order what?'). The two expressions are equally polite; however, the latter is more sympathetic and friendly. When conversing with family and relatives, most Indonesians also prefer using kinship terminology (father, mother, brother, sister) when addressing older family members. When addressing younger family members, informal pronouns are more prevalent.

Verb forms English lacks some grammatical categories which are present in some other languages.

There is no simple way in English to contrast Finnish or Polish (continuing, corresponding to English 'to write') with or (a regular frequentative, 'to occasionally write short passages at a time', or 'to jot down now and then'). Similarly, and (to jump once) contrast with and (to continuously jump; to be jumping from point A to B).

Irish allows the prohibitive mood to be used in the passive voice. The effect is used to prohibit something while expressing society's disapproval for that action at the same time. For example, contrast (meaning 'Don't smoke' when said to more than one person), which uses the second person plural in the imperative meaning "Do not smoke", with (best translated as 'Smoking just isn't done here'), which uses the autonomous imperative meaning 'One does not smoke'.

Italian has three distinct declined past tenses: thus (), (), and () all mean 'I was'. The first indicates a concluded action in the (remote) past, the second a progressive or habitual action in the past, and the latter an action that holds some connection to the present, especially if a recent time is specified ("" for 'this morning I saw'). The is often used for narrative history (for example, novels). Nowadays, the difference between and is blurred in the spoken language, the latter being used in both situations. What difference there exists is partly geographic. In the north of Italy the is very rarely used in everyday speech, whereas in the south it often takes the place of the . The distinction is only alive in Tuscany, which makes it dialectal even if hardline purists insist it should be applied consistently.

Likewise, English lacks a productive grammatical means to show indirection but must instead rely on periphrasis, that is the use of multiple words to explain an idea. Finnish grammar, on the contrary, allows the regular production of a series of verbal derivatives, each of which involves a greater degree of indirection. For example, on the basis of the verb ('to pull'), it is possible to produce: (pull), (cause something/someone to pull/to wind-up (lie)), (cause something/someone to cause something/someone to pull), (cause something/someone to cause something/someone to cause something/someone to pull).

Finnish English Translation/paraphrase of boldface verb Hevonen vetää. A horse pulls. pulls Ajomies vedättää. A driver commands the horse to pull. causes something to pull Urakoitsija vedätyttää. A subcontractor directs the driver to command the horse to pull. causes someone to cause something to pull Yhtiö vedätätyttää. The corporation assigns the subcontractor to have the driver command the horse to pull. causes someone to cause someone to cause something to pull

Hindi has a similar concept of indirection. means 'to do'; means 'to make someone do'; means 'to get someone to make yet another person do'.

Most Turkic languages (Turkish, Azeri, Kazakh) contain the grammatical verb suffix miş (or mis in other dialects), which indicates that the speaker did not witness the act personally but surmises or has discovered that the act has occurred or was told of it by another, as in the example of (Turkish), which can be expressed in English as "it is reported that he/she/it has gone", or, most concisely, as "apparently, he/she/it has gone". This grammatical form is especially used when telling jokes, or narrating stories.

Similar to the Turkic miş, nearly every Quechua sentence is marked by an evidential clitic, indicating the source of the speaker's knowledge (and how certain they are about the statement). The enclitic =mi expresses personal knowledge (Tayta Wayllaqawaqa chufirmi, "Mr. Huayllacahua is a driver - I know it for a fact"); =si expresses hearsay knowledge (Tayta Wayllaqawaqa chufirsi, "Mr. Huayllacahua is a driver, or so I've heard"); =chá expresses high probability (Tayta Wayllaqawaqa chufirchá, "Mr. Huayllacahua is a driver, most likely"). Colloquially, the latter is also used when the speaker has dreamed the event told in the sentence or experienced it while intoxicated.

Languages that are extremely different from each other, like English and Chinese, need their translations to be more like adaptations. Chinese has no tenses per se, only three aspects. The English verb "to be" does not have a direct equivalent in Chinese. In an English sentence where "to be" leads to an adjective ("It is blue"), there is no "to be" in Chinese. (There are no adjectives in Chinese, instead there are stative verbs that do not need an extra verb.) If it states a location, the verb () is used, as in "We are in the house". In some other cases (usually when stating a judgement), the judgment verb () is used, as in "I am the leader." And in most other cases, such structure ("to be") is simply not used, but some more natural structure in Chinese is used instead. Any sentence that requires a play on those different meanings will not work the same way in Chinese. In fact, very simple concepts in English can sometimes be difficult to translate, for example, there is no single direct translation for the word "yes" in Chinese, as in Chinese the affirmative is said by repeating the verb in the question. ("Do you have it?" "(I) have".)

Vocabulary German, Dutch, and Danish have a wealth of modal particles that are particularly difficult to translate as they convey sense or tone rather than strictly grammatical information. The most infamous example perhaps is (Dutch: , Danish: ), which roughly means "Don't you realize that . . . ?" or "In fact it is so, though someone is denying it." What makes translating such words difficult is their different meanings depending on intonation or the context.

A common use of the word can be found in the German sentence , which translates to The war wasn't lost yet, after all or The war was still not lost.

Several other grammatical constructs in English may be employed to translate these words for each of their occurrences. The same with slightly changed pronunciation can also mean excuse in defense to a question: . . . but the war was not lost yet (. . . so we fought on).

A use which relies heavily on intonation and context could produce yet another meaning: "So the war was really not over yet (as you have been trying to convince me all along)."