A variation of the pointed cross, the heraldic
dagger is a common sign
in printed texts.
In typography the sign , along with and , is used as a sign for note, i.e. an amendment to the main text.
In botany the dagger means poisonous, in chess, check! In timetables it is sometimes used for Sunday or holiday. In genealogy it is used for deceased or dead. In dictionaries it can indicate an obsolete word, and again in botany it may mean a once cultivated but now wild growing plant.
This sign is the second in series of reference marks and as such called obelisk or obelus. See reference marks in the word index for the other signs.
The dagger is also sometimes used preceding a death date, that is meaning dead or died.