2885: Rickets is not from Rachitis Nov 14, 2024

The disease known as rickets, a lack of vitamin D leading to soft bones, is known in New Latin as Rachitis, from the Greek ῥαχίτης (rhakhítēs) , but those terms as names for the disease actually come, in part, from English rather than the other way around as one might expect. To be clear, the Ancient Greek ῥαχίτης (rhakhítēs) does exist, and obviously before English, meaning ‘spine’, but this is not the origin of the term rickets. 

It is not entirely clear where this term comes from, other than that it was a local term used in Southeastern England after which Daniel Whistler named it in the 17th century. He took the English term, backformed it from a semantically related Greek term, and developed the New Latin word Rachitis, which is also used in some modern languages now like German. 

This is also where the term ‘rickety’ comes from, in the sense of having weak structural support.