A necronym (from the Greek words νεκρός, nekros, "dead" and ὄνομα ónoma, "name") is a reference to, or name of, a person who has died. Many cultures have taboos and traditions associated with referring to such a person. These vary from the extreme of never again speaking the person's real name, often using some circumlocution instead, to the opposite extreme of commemorating it incessantly by naming other things or people after the deceased.
For instance, in some cultures it is common for a newborn child to receive the name (a necronym) of a relative who has recently died, while in others to reuse such a name would be considered extremely inappropriate or even forbidden. While this varies from culture to culture, the use of necronyms is quite common.
Composer Ludwig van Beethoven, born in 1770, had a brother named Ludwig Maria who was born in 1769 and lived for only six days. Vincent van Gogh had a brother of the same name who was born, and died, on March 30, 1852, exactly one year before the painter's birth. The artist Salvador Dalí was born nine months and ten days after his brother, also named Salvador, died from gastroenteritis at the age of one year and nine months.
In Ashkenazi Jewish culture, it is a custom to name a child after a beloved relative who died as a way of honoring the deceased. Often the child will share the same Hebrew name as the namesake but not the given name in the vernacular language (e.g. English).
In Japan, Buddhist families usually obtain a necronym, called a kaimyō, for a deceased relative from a Buddhist priest in exchange for a donation to the temple. Traditionally, the deceased were thereafter referred to by the necronym, as a sign of pious respect. This name was often the only one inscribed on gravestones in the past, though now it is more common to have the necronym in addition to the given name.
Necronyms were also commonly used during the Cold War as a means of protecting an intelligence officer's true identity. For example, the Soviet KGB agent Konon Molody was only known as Gordon Lonsdale (the true Lonsdale was a Canadian born two years after Molody and died in 1943 when he was 19) in the United States. Molody adopted the name when he was 32, 11 years after the real Lonsdale's death.
The practice of bestowing necronyms has sometimes caused confusion for historians. This is primarily because of the two birth certificates or records that could be present at a given time. This confusion often stems from the inability to differentiate the records of each child. One such example is the case of Shigechiyo Izumi (1865?–1986), accepted in 1986 as the world's oldest man by The Guinness Book of World Records, but who was in fact possibly born in 1880, after one previous brother whose name he assumed upon his death.