Chillies n Garlic The English names chile or chilli are borrowed from Náhuatl (native Mexican), where the plant’s...

Chillies n Garlic The English names chile or chilli are borrowed from Náhuatl (native Mexican), where the plant’s name chilli allegedly derived from a root meaning red.

It is not related to the country name Chile, which is supposed to derived from the Quechua word meaning end, because today’s Chile marks the southern end of the Inca Empire.

Another theory links the toponym to an Araucanian term depth referring to the coastal lowlands as seen from the Andes.
Capsicum cardenasii: Ulupica flower
Flower of Bolivian ulupica chile (Capsicum cardenasii)

There is con­siderable zeal in the discussion whether the spice should be called
Chile
Chili
or chilli in English.
The form chilli is probably closest to the Náhuatl original, and it is the preferred form among historically minded USians and in Australia.

The word chili has come to mean almost exclusively the Tex-Mex-food chili con carne in the USA, but is used for the spice in British English.

The variant chilly (also the adverb of chill) has become obsolete; it bears connotations to the British Colonial Era and sometimes appears in brand names of products that go back to the first half of the 20.th century.
Lastly, chile is the name of the spice in contemporary Mexican Spanish, and it is also quite popular in the USA.

To make things worse, chiles are often referred to as peppers in English, which is of course a never-ending source of culinarily fatal misunderstandings.