These Linguists Are Creating a New Dictionary of Ancient Celtic Languages—With Help From ‘Curse Tablets’ and Roman Records

The project aims to produce a record of the Celtic languages spoken in Britain and Ireland, though the majority of these words have already been lost to history

Sonja Anderson

– Daily Correspondent

December 19, 2025 4:40 p.m.

Researchers say they are compiling the first-ever dictionary of ancient Celtic languages in Britain and Ireland. Led by Simon Rodway, a linguist at Aberystwyth University in Wales, the project aims to document the surviving words from languages that have been largely lost to history.

So far, the researchers have collected more than 1,000 words—“just a tiny little glimpse into the language,” Rodway tells Ailsa Chang of NPR’s “All Things Considered.” “We’re not going to get many more than that because the records of the Celtic languages in Britain and Ireland are not great.”

The researchers are gathering material from ancient inscriptions and texts, according to a statement from the university. Their dictionary will include words from about 325 B.C.E. through 500 C.E., reports the Guardian’s Steven Morris. This period includes the Roman Empire’s rule in Britain, which lasted from 43 to 410 C.E.

“The Romans were very literate,” Rodway tells “All Things Considered.” “They wrote everything down. They were hugely bureaucratic, so we have a lot of letters. We’ve got legal stuff. We’ve got inscriptions.”

These Roman sources, written in Latin or Greek, contain Celtic names of places, ethnic groups and individuals, Rodway tells the Guardian. They include letters written by Roman soldiers and Julius Caesar’s accounts of his northern European conquests.

Some key inscriptions are found on stones in Cornwall and Ireland. These writings use the Ogham alphabet, which features letters made of straight lines. Other interesting sources include a group of four or five texts written entirely in ancient Celtic, which Rodway calls “curse tablets.” These lead panels were engraved by Celts who were wronged and wanted revenge.

᚛ᚈᚑᚋ ᚄᚉᚑᚈᚈ᚜ and ᚛ᚑᚌᚐᚋ᚜

“Mostly, they’re curses against thieves who have stolen the belongings of people, particularly in Bath,” Rodway tells “All Things Considered.”

Around 70 C.E., Roman settlers built bathhouses above geothermal springs in the city now known as Bath. The baths attracted both tourists and thieves, Rodway says. Apparently, bathers would exit the pools to find their clothes had been stolen.

“What they’d do then is they would find somebody who had a sheet of lead, and they’d scratch a curse on that lead tablet, asking a god or a goddess to do all sorts of horrible things to the person who’d taken their belongings,” Rodway adds. “And they’d throw that into the spring, which was consecrated to the goddess.”

The researchers will compare their collection of ancient Celtic words to the medieval and modern Celtic languages. Per the statement, today’s Celtic languages are very different from each other, but there are some similarities. For example, the Welsh and Old Irish words for “sea”—môr and muir—correspond with moridunum, an ancient Celtic word meaning “sea fort,” reports the Guardian.

“It’s extremely exciting to lead this project and pen the first dictionary of this kind,” Rodway says in the statement. “These disparate sources have never before been brought together in a way that offers such a comprehensive insight into the nature of Celtic languages spoken in these islands at the dawn of the historical period.”