Combining grapheme joiner

The combining grapheme joiner (CGJ), U+034F ͏ COMBINING GRAPHEME JOINER is a Unicode character that has no visible glyph and is "default ignorable" by applications. Its name is a misnomer and does not describe its function: the character does not join graphemes.^[1] Its purpose is to semantically separate characters that should not be considered digraphs as well as to block canonical reordering of combining marks during normalization.

For example, in a Hungarian language context, adjoining letters c and s would normally be considered equivalent to the cs digraph. If they are separated by the CGJ, they will be considered as two separate graphemes. However, in contrast to the zero-width joiner and similar characters, the CGJ does not affect whether the two letters are rendered separately or as a ligature or cursively joined—the default behavior for this is determined by the font.^[2]

The CGJ is also needed for complex scripts. For example, in most cases the Hebrew cantillation accent metheg is supposed to appear to the left of the vowel point and by default most display systems will render it like this even if it is typed before the vowel. But in some words in Biblical Hebrew the metheg appears to the right of the vowel, and to tell the display engine to render it properly on the right, CGJ must be typed between the metheg and the vowel. Compare:

UnicodeCode pointsCharacters

Special purpose	BOM Combining grapheme joiner Left-to-right mark / Right-to-left mark Soft hyphen Variant form Word joiner Zero-width joiner Zero-width non-joiner Zero-width space
Lists	Characters CJK Unified Ideographs Combining character Duplicate characters Numerals Scripts Spaces Symbols Halfwidth and fullwidth Alias names and abbreviations Whitespace characters

Processing

Algorithms	Bidirectional text Collation ISO/IEC 14651 Equivalence Variation sequences International Ideographs Core
Comparison of encodings	BOCU-1 CESU-8 Punycode SCSU UTF-1 UTF-7 UTF-8 UTF-16/UCS-2 UTF-32/UCS-4 UTF-EBCDIC

On pairs of
code pointsUsageRelated standardsRelated topics

Scripts and symbols in Unicode
Common and inherited scripts	Combining marks Diacritics Punctuation marks Spaces Numbers
Modern scripts	Adlam Arabic Armenian Balinese Bamum Batak Bengali Bopomofo Braille Buhid Burmese Canadian Aboriginal Chakma Cham Cherokee CJK Unified Ideographs (Han) Cyrillic Deseret Devanagari Geʽez Georgian Greek Gujarati Gunjala Gondi Gurmukhi Hangul Hanifi Rohingya Hanja Hanunuoo Hebrew Hiragana Javanese Kanji Kannada Katakana Kayah Li Khmer Lao Latin Lepcha Limbu Lisu (Fraser) Lontara Malayalam Masaram Gondi Mende Kikakui Medefaidrin Miao (Pollard) Mongolian Mru N'Ko Nag Mundari New Tai Lue Nüshu Nyiakeng Puachue Hmong Odia Ol Chiki Osage Osmanya Pahawh Hmong Pau Cin Hau Pracalit (Newa) Ranjana Rejang Samaritan Saurashtra Shavian Sinhala Sorang Sompeng Sundanese Syriac Tagbanwa Tai Le Tai Tham Tai Viet Tamil Tangsa Telugu Thaana Thai Tibetan Tifinagh Tirhuta Toto Vai Wancho Warang Citi Yi
Ancient and historic scripts	Ahom Anatolian hieroglyphs Ancient North Arabian Avestan Bassa Vah Bhaiksuki Brāhmī Carian Caucasian Albanian Coptic Cuneiform Cypriot Cypro-Minoan Dives Akuru Dogra Egyptian hieroglyphs Elbasan Elymaic Glagolitic Gothic Grantha Hatran Imperial Aramaic Inscriptional Pahlavi Inscriptional Parthian Kaithi Kawi Kharosthi Khitan small script Khojki Khudawadi Khwarezmian (Chorasmian) Linear A Linear B Lycian Lydian Mahajani Makasar Mandaic Manichaean Marchen Meetei Mayek Meroitic Modi Multani Nabataean Nandinagari Ogham Old Hungarian Old Italic Old Permic Old Persian cuneiform Old Sogdian Old Turkic Old Uyghur Palmyrene ʼPhags-pa Phoenician Psalter Pahlavi Runic Sharada Siddham Sogdian South Arabian Soyombo Sylheti Nagri Tagalog (Baybayin) Takri Tangut Ugaritic Vithkuqi Yezidi Zanabazar Square
Notational scripts	Duployan SignWriting
Symbols, emojis	Cultural, political, and religious symbols Currency Control Pictures Mathematical operators and symbols List by subject Phonetic symbols (including IPA) Emoji
Category: Unicode  Category: Unicode blocks