The zero-width non-joiner (ZWNJ, ; rendered: ; HTML entity: or) is a non-printing character used in the computerization of writing systems that make use of ligatures. When placed between two characters that would otherwise be connected into a ligature, a ZWNJ causes them to be printed in their final and initial forms, respectively. This is also an effect of a space character, but a ZWNJ is used when it is desirable to keep the characters closer together or to connect a word with its morpheme.
The ZWNJ is encoded in Unicode as .
In certain languages, the ZWNJ is necessary for unambiguously specifying the correct typographic form of a character sequence.
| Correct (with ZWNJ) | Incorrect | Meaning | |||||
|---|---|---|---|---|---|---|---|
| Display | Picture | Code | Display | Picture | Code | ||
می‌خواهم(rendered from right to left):
| میخواهم | Persian 'I want to' | |||||
ساءين‌س(rendered from right to left):
| ساءينس | Malay 'science' | |||||
הֱ‌ֽיֹות(rendered from right to left):
| הֱֽיֹות | Old Hebrew 'be' | |||||
| German: 2=<span style="font-family:serif; font-size:x-large;">Auflage</span>|italic=no | Auf&zwnj;lage | German: 2=<span style="font-family:serif; font-size:x-large;">Auflage</span>|italic=no | Auflage | German 'edition' (compound of "German: auf"+"German: Lage") | |||
Brot&zwnj;zeit | Brotzeit | German (regional) '(kind of) snack' (compound noun "German: Brot"+"German: Zeit" = 'bread time'), shown in Fraktur | |||||
| deafly | deaf&zwnj;ly | deafly | deafly | Not a compound of "dea"+"fly", but the adverb of "deaf" | |||
| Nepali: 2=<span style="font-family:serif; font-size:x-large">श्रीमान्को</span> | श्रीमान्&zwnj;को | Nepali: 2=<span style="font-family:serif; font-size:x-large">श्रीमान्को</span> | श्रीमान्को | In Nepali "of husband" or "of respected person" according as what "श्रीमान्" is used to represent (husband or respected person). | |||
| Bengali: 2=<span style="font-family:serif; font-size:x-large">উদ্যাপন</span> | উদ্&zwnj;যাপন | Bengali: 2=<span style="font-family:serif; font-size:x-large">উদ্যাপন</span> | উদ্যাপন | Bengali meaning of celebration. | |||
| Nepali: 2=<span style="font-family:serif; font-size:x-large">अय्लाः</span> | अय्&zwnj;लाः | Nepali: 2=<span style="font-family:serif; font-size:x-large">अय्लाः</span> | अय्लाः | Wine in Nepalbhasa | |||
| Telugu: 2=<span style="font-family:serif; font-size:x-large">హైద్రాబాద</span> | హైద్&zwnj;రాబాదు | Telugu: 2=<span style="font-family:serif; font-size:x-large">హైద్రాబాదు</span> | హైద్రాబాదు | Hyderabad written in Telugu | |||
In this Biblical Hebrew example, the placement of the Hebrew: [[meteg]] to the left of the Hebrew: [[segol]] is correct, which has a Hebrew: shva sign written as two vertical dots to denote short vowel. If a Hebrew: meteg were placed to the left of Hebrew: shva, it would be erroneous. In Modern Hebrew, there is no reason to use the Hebrew: meteg for spoken language, so it is rarely used in Modern Hebrew typesetting.
In German typography, ligatures may not cross the constituent boundaries within compounds. Thus, in the first German example, the prefix German: Auf- is separated from the rest of the word to prohibit the ligature fl. Similarly, in English, some argue ligatures should not cross morpheme boundaries.[1] For example, in some words fly and fish are morphemes but in others they're not; therefore, by their reasoning, words like and (here shown with the non-joiner) should not have ligatures (respectively of fl and fi) while dayfly and catfish should have them.
Persian uses this character extensively for certain prefixes, suffixes and compound words.[2] It is necessary for disambiguating compounds from non-compound words, which use a full space.
In the Jawi script of Malay, ZWNJ is used whenever more than one consonants are written at the end of any phrase (Malay: سا{{Jawi-HamzaThreeQuarter, Malay for 'science' or Malay: sains in Latin script, pronounced /ˈsa.ɪns/.) It is used to signify that there are no vowels (specifically 'a' or 'ə') in between the two consonant letters as Malay: سا{{Jawi-HamzaThreeQuarter would otherwise be pronounced either /ˈsa.ɪnas/ or /ˈsa.ɪnəs/. A space would separate the phrase into different words, where phrases such as Malay: سا{{Jawi-HamzaThreeQuarter would now mean 'to sign the Arabic letter sin' (Malay: sain sin in Latin script.)
In Indic scripts, insertion of a ZWNJ after a consonant either with a halant or before a dependent vowel prevents the characters from being joined properly:[3]
In Devanagari, the characters and typically combine to form, but when a ZWNJ is inserted between them, (code: क्&zwnj;ष) is seen instead.
In Kannada, the characters ನ್ and ನ combine to form ನ್ನ, but when a ZWNJ is inserted between them, ನ್ನ is displayed. That style is typically used to write foreign words in Kannada script: "Facebook" is written as ಫೇಸ್ಬುಕ್, though it can be written as ಫೇಸ್ಬುಕ್. ರಾಜ್ಕುಮಾರ್ and ರಾಮ್ಗೊಪಾಲ್ are examples of other proper nouns that need ZWNJ.
To insert a ZWNJ in Kannada, use Shift-V on Linux (iBus, InScript). On Windows (InScript), you can produce a ZWNJ with Ctrl+Shift+2 or Alt+0157. For the LipikaIME on Mac, the caret returns a ZWNJ.
In Bengali, when the Bengali letter য occurs at the end of a consonant cluster—i.e., য preceded by a ◌্ (hôsôntô)—it appears in a special shape,, known as the য-ফলা (ja-phala), such as in ক্য (ক ্ য). Thus, when we want to write উদ্যাপন (correct Bengali spelling for celebration), it becomes উদ্যাপন (which is incorrect). Here ZWNJ works. If we want to write উদ্যাপন, we have to write in the following sequence (code: উদ্‌যাপন),[4] [5] then we will get the proper rendering and the correct spelling. In Bengali, the hôsôntô is used for making any conjuncts and falas (such as ra-fala, ba-fala etc). Where the hôsôntô needs to be displayed explicitly, it is required to insert ZWNJ after the hôsôntô.
Also in Bengali, when the Bengali letter র occurs at the beginning of a consonant cluster—i.e., র succeeded by a hôsôntô—it appears in a special shape, known as the রেফ (reph). Thus, the sequence র ্ য is rendered by default as র্য. When the য-ফলা shape needs to be retained rather than the রেফ shape, the ZWJ is inserted right after র, i.e., র‍্য to render র্য. র্য is commonly used for loanwords from English such as র্যাম (RAM), র্যান্ডম (random) etc.
The symbol to be used on keyboards which enable the input of the ZWNJ directly is standardized in Amendment 1 (2012) of ISO/IEC 9995-7:2009 "Information technology – Keyboard layouts for text and office systems – Symbols used to represent functions" as symbol number 81, and in IEC 60417 "Graphical Symbols for use on Equipment" as symbol no. IEC 60417-6177-2.