Anglo-Norman words

In an Anglo-Norman prose lapidary from the second half of the thirteenth century – a study of the medical ‘powers’ of different stones and minerals, claiming to derive its knowledge from a letter which  the mysterious Arabian king Evax  wrote  to Emperor Tiberius – we find the following recommendation: “La rousse [celidoine] est bone a houme qui chiet de passion et a home lunage”  Lapid  149.xxvi.7 (“The red [chelidonius] (=a small stone taken from the gizzard of a swallow) is good for someone who suffers epilepsy and for a ‘lunatic’ person”) Leaving aside the question of how effective the use of a piece of red chelidonius would have been in these matters, we would like to concentrate on the word lunage . The adjective derives from lune  (Latin luna : ‘moon’), followed by the (normally substantival) suffix - age , and is the Anglo-Norman equivalent to Latin lunaticus . This particular word formation is no longer extant in Modern French ...