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A dagger (†, †, U+2020) is a typographical symbol or glyph. It is also called a cross, obelos, or obelus. The term "obelus" is derived from a Greek word meaning "roasting spit", "needle", or "obelisk".

A double dagger (‡, ‡, U+2021) is a variant with two handles; this is also called a diesis.

[edit] History

The symbol was first used in liturgical books of the Roman Catholic Church, marking a minor intermediate pause in the chanting of Psalm verses (the major intermediate pause was marked with an asterisk) or the point at which the chanting of the Psalm was taken up after an introductory antiphon whose words were identical to the opening words of the Psalm.

[edit] Usage

The dagger is usually used to indicate a footnote, in the same way an asterisk is. However, the dagger is only used for a second footnote when an asterisk is already used. A third footnote employs the double dagger. Additional footnotes are somewhat inconsistent and represented by a variety of symbols, e.g., parallels (||) and the pilcrow (¶), some of which were nonexistent in early modern typography. Partly because of this, superscript numerals 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 should not be confused with the "box drawings light vertical and horizontal" (┼, U+253C) nor palatal click (IPA: [ǂ], U+01C2).

Since it also represents the Christian cross, in certain predominantly Christian regions, the mark is used in a text before or after the name of a deceased person or the date of death, as in Christian grave headstones. For this reason, it should not be used as a footnote mark next to the name of a living person.

[edit] Other Uses of Daggers

Listed below are other possible uses of daggers:

• In mathematics and, more often, physics, a dagger is used to denote 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.^[1]

• In textual criticism and in some editions of works written before the invention of printing, daggers are used to enclose text that is believed not to be original.

• In historical linguistics, daggers are used to indicate invalid reconstructions. The notation is used when non-attested words are reconstructed for the sake of argument only, implying that the author does not believe such a word or word form has ever existed.

• In biology, the dagger next to a taxon name indicates that taxon is extinct.

• In chess notation, the dagger may be suffixed to a move to signify the move resulted in a check, and a double dagger is used to denote checkmate. This is a stylistic variation on the more common '+' (plus sign) for a check and '++' (double plus) or '#' (octothorpe) for checkmate.

• In chemistry, the double dagger is used in chemical kinetics to indicate a transition state species.

• In psychological statistics the dagger is used to indicate that a difference between two figures isn't significant to a p<0.05 level, however is still considered a 'trend' or worthy of noting. Commonly this will be used for a p-value between 0.1 and 0.06.

• On a cricket scorecard or team list, the dagger indicates the team's wicket-keeper^[2]

• In military history, a dagger is often placed next to the name of a commander who is killed in action.

• The double dagger should not be confused with the cross of Lorraine or the patriarchal cross.

Dagger and double-dagger symbols in a variety of fonts, showing the differences between stylized and non-stylized characters

[edit] References

1. ^ http://mathworld.wolfram.com/Dagger.html
2. ^ http://content-aus.cricinfo.com/wc2007/engine/current/match/247499.html