The fruit, known botanically as Citrus hystrix, is native to Sri Lanka and is also found in Mauritius and Southeast Asia, including Thailand, where it is known as Makrut.
The word is believed to come from Arabic, where kafir means infidel or unbeliever and is derogatory.
Scottish botanist HF MacMillan is believed to have introduced the fruit to the English-speaking world, using the Kaffir lime name in the late 1800s.
The word was also used in apartheid South Africa as an anti-black insult and considered as bad as the N word.
It again emerged as an offensive term for the Nguni peoples of South East Africa.
Thomas Hickock in 1588 used the word to describe them, claiming that the Nguni traders were “cafe merchants”, although in this case it was not believed to have been crudely meant, much like the way people are called ‘British’ or ‘Swedish’ today.
He considered it a natural way to write about them. Despite this, the word was used by Muslims in Africa to describe the people.
But over the following years, the use of the word became well known as offensive. There are examples of its use in this way from 1820.
The fruit, known botanically as Citrus hystrix, is native to Sri Lanka and is also found in Mauritius and Southeast Asia, including Thailand, where it is known as Makrut (photo by archives)
This despite the fact that these people were a political entity at this stage and were sometimes even referred to as “British Kaffraria” during the time of the empire.
It is not known when the word changed from neutral to offensive towards the Nguni.
In 1607, William Keeling of the East India Company loosely used it as “Cafares” for the inhabitants of the Cape of Good Hope. Again, however, we don’t think he thinks it in a negative light.
But because of the word commonly used to describe people on the mainland, it was believed recipients found it offensive.
It came to be seen as a highly inflammatory word meaning “inferior” and “shoddy”. It turned into phrases such as “kaffir-lover” and “Kaffirboetie” for a white person close to a black person.
In the 20th century, it was cemented as a derogatory term. From 1950 the word was commonly used by whites in South Africa against blacks.
The country now bans the word and legal action can be taken if it is used. Locals are often shocked to see its use in cookbooks overseas.
In 2018, a woman was jailed there for abusing a black policeman with the word.
Many chefs and food writers in Britain, Australia, and the United States have chosen to adopt the name Makrut for the fruit instead.