A dagger (†, †, U+2020) is a typographical symbol or glyph. It is also called an obelos, from a Greek word meaning "roasting spit" or "needle"; or obelisk, an alteration of the above (see obelisk). A double dagger (‡, ‡ U+2021) is a variant with two "handles", and is also called a diesis.

The symbol was first used in rubrics of Roman Catholic liturgy, marking points at which the priest had to make the sign of the cross.

The dagger is used to indicate a footnote, in the same way an asterisk is. However, the dagger is only used as a second footnote when an asterisk is already used. Third footnote employs the double daggers. Additional footnotes are somewhat inconsistent and represented by a variety of symbols, e.g., parallels (||) and the pilcrow (¶), some of which are nonexistent in early modern typography. Partly due to this, in modern literature, superscript numerals are used in the place of pictorial symbols. Some texts use asterisks and daggers alongside superscripts, using the former for per-page footnotes and the latter for endnotes.

Sometimes it is replaced in ASCII by a plus sign (+).

Since it also represents the Christian cross, in certain predominantly Christian regions, the mark is used in a text 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.

In European railway timetables, the dagger (Christian cross) is frequently used as a conventional sign meaning "Sundays and holidays".

In taxonomical nomenclature, the dagger symbol is used to denote extinct taxa.

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.

In textual criticism, and hence some editions of dated texts, daggers are used to enclose disputed text.

In some forms of chess notation the double dagger is used to denote checkmate.

Trivia

• The names of the comic-book heroes Astérix and Obélix come from a pun on the French names of the asterisk and the obelisk.

Typography | Punctuation

Dagger | Kreuz (Schriftzeichen) | Obèle | Obelisk (leesteken) | 短剣符 | Risti (merkki) | Kors (tecken) | 剑标