A dagger, obelisk, or obelusTemplate:Serif is a typographical mark that usually indicates a footnote if an asterisk has already been used.<ref name="partridge" /> The symbol is also used to indicate death (of people) or extinction (of species or languages).<ref>Template:Cite web</ref> It is one of the modern descendants of the obelus, a mark used historically by scholars as a critical or highlighting indicator in manuscripts. In older texts, it is called an obelisk.<ref>Template:Cite dictionary</ref>Template:Efn
A double dagger, or diesis, Template:Char is a variant with two hilts and crossguards that usually marks a third footnote after the asterisk and dagger.<ref name="H&F" /> The triple daggerTemplate:Char is a variant with three crossguards and is used by medievalists to indicate another level of notation.<ref name="L215327">Template:Cite web</ref>
The dagger symbol originated from a variant of the obelus, originally depicted by a plain line Template:Char or a line with one or two dots Template:Char.<ref name="merriamw">Template:Cite book</ref> It represented an iron roasting spit, a dart, or the sharp end of a javelin,<ref name="ainsw">Template:Cite book</ref> symbolizing the skewering or cutting out of dubious matter.<ref name="scanlin" /><ref name="enc" /><ref name="hamann" />
While the asterisk (asteriscus) was used for corrective additions, the obelus was used for corrective deletions of invalid reconstructions.<ref name="BHS">Template:Cite book</ref> It was used when non-attested words are reconstructed for the sake of argument only, implying that the author did not believe such a word or word form had ever existed. Some scholars used the obelus and various other critical symbols, in conjunction with a second symbol known as the metobelos ("end of obelus"),<ref name="metobelus">Template:Cite web</ref> variously represented as two vertically arranged dots, a Template:Char-like symbol, a mallet-like symbol, or a diagonal slash (with or without one or two dots). They indicated the end of a marked passage.<ref name="wurth">Template:Cite book</ref>
It was used much in the same way by later scholars to mark differences between various translations or versions of the Bible and other manuscripts.<ref name="garrison">Template:Cite book</ref> The early ChristianAlexandrian scholar Origen (Template:Circa AD) used it to indicate differences between different versions of the Old Testament in his Hexapla.<ref name="wegner" /><ref name="metobelus" /><ref name="jones">Template:Cite book</ref> Epiphanius of Salamis (c. 310–320 – 403) used both a horizontal slash or hook (with or without dots) and an upright and slightly slanting dagger to represent an obelus. St. Jerome (c. 347–420) used a simple horizontal slash for an obelus, but only for passages in the Old Testament.<ref name="smith&wace">Template:Cite book</ref> He describes the use of the asterisk and the dagger as: "an asterisk makes a light shine, the obelisk cuts and pierces".<ref name="hamann">Template:Cite book</ref>
Isidore of Seville (c. 560–636) described the use of the symbol as follows: "The obelus is appended to words or phrases uselessly repeated, or else where the passage involves a false reading, so that, like the arrow, it lays low the superfluous and makes the errors disappear ... The obelus accompanied by points is used when we do not know whether a passage should be suppressed or not."<ref name="enc">Template:Cite book</ref>
Medieval scribes used the symbols extensively for critical markings of manuscripts. In addition to this, the dagger was also used in notations in early Christianity, to indicate a minor intermediate pause in the chanting of Psalms, equivalent to the quaver rest notation or the trope symbol in Hebrew cantillation. It also indicates a breath mark when reciting, along with the asterisk, and is thus frequently seen beside a comma.<ref name="fenlon">Template:Cite book</ref><ref name="seiyaku">Template:Cite web</ref>
In the 16th century, the printer and scholar Robert Estienne (also known as Stephanus in Latin and Stephens in English) used it to mark differences in the words or passages between different printed versions of the Greek New Testament (Textus Receptus).<ref name="martin">Template:Cite book</ref>
Due to the variations as to the different uses of the different forms of the obelus, there is some controversy as to which symbols can actually be considered an obelus. The Template:Char symbol and its variant, the Template:Char, is sometimes considered to be different from other obeli. The term 'obelus' may have referred strictly only to the horizontal slash and the dagger symbols.Template:Cn
The dagger usually indicates a footnote if an asterisk has already been used.<ref name="partridge" /> A third footnote employs the double dagger.<ref name="H&F">Template:Cite web</ref> Additional footnotes are somewhat inconsistent and represented by a variety of symbols, e.g., parallels ( Template:Larger ), section signTemplate:Char, and the pilcrowTemplate:CharTemplate:Snd some of which were nonexistent in early modern typography. Partly because of this, superscriptnumerals have increasingly been used in modern literature in the place of these symbols, especially when several footnotes are required. Some texts use asterisks and daggers alongside superscripts, using the former for per-page footnotes and the latter for endnotes.
The dagger is also used to indicate death,<ref name="H&F" /><ref name="reynolds" /> extinction,<ref name="tudge" /> or obsolescence.<ref name="partridge">Template:Cite book</ref><ref name="oedguide" /> The asterisk and the dagger, when placed beside years, indicate year of birth and year of death respectively.<ref name="H&F" /> This usage is particularly common in German.<ref>Template:Cite book</ref> When placed immediately before or after a person's name, the dagger indicates that the person is deceased.<ref name="H&F" /><ref name="knowles">Template:Cite book</ref><ref name="campbell">Template:Cite book</ref><ref name="lennard">Template:Cite book</ref> In this usage, it is referred to as the "death dagger".<ref name="aps">Template:Cite web</ref> Death-related usages include:
In chemistry, the double dagger is used in chemical kinetics to indicate a short-lived transition state species.
In genealogy, the dagger is used traditionally to mark a death in genealogical records.<ref>Template:Cite web</ref>
In chess notation, the dagger may be suffixed to a move to signify the move resulted in a check, and a double dagger denotes checkmate. This is a stylistic variation on the more common Template:Char (plus sign) for a check and Template:Char (number sign) for checkmate.
In linguistics, the dagger placed after a language name indicates an extinct language.
In philology, the dagger indicates an obsolete form of a word or phrase.<ref name="partridge" /> As language that has become obsolete in everyday use tends to live on elsewhere, the dagger can indicate language only occurring in poetical texts<ref>Template:Cite book</ref> or "restricted to an archaic, literary style".<ref>Template:Cite book</ref>
The asteroid 37 Fides, the last asteroid to be assigned an astronomical symbol before the practice faded, was assigned the dagger.
In Anglican chant pointing, the dagger indicates a verse to be sung to the second part of the chant.
In some early printed Bible translations, a dagger or double dagger indicates that a literal translation of a word or phrase is to be found in the margin.
In library cataloging, a double dagger delimits MARC subfields.
The palochka is transliterated to a double dagger in the ISO 9 standard for converting Cyrillic to Latin
In psychological statistics the dagger indicates that a difference between two figures is not significant to a p<0.05 level, however is still considered a "trend" or worthy of note. Commonly this will be used for a p-value between 0.1 and 0.05.
In mathematics and, more often, physics, a dagger denotes the Hermitian adjoint of an operator; for example, A† denotes the adjoint of A. This notation is sometimes replaced with an asterisk, especially in mathematics. An operator is said to be Hermitian if A† = A.<ref>Template:MathWorld</ref>
In textual criticism and in some editions of works written before the invention of printing, daggers enclose text that is believed not to be original.<ref name="wegner" />
While daggers are freely used in English-language texts, they are often avoided in other languages because of their similarity to the Christian cross.Template:Citation needed
