Extract from Mayo - Aspects of it's Heritage
Claremorris (1,718 ) Clar Chainne Mhuiris (‘the plain of Clann Mhuiris’)
The form Claremorris does not seem to have appeared on a map until about 1868; the form on the first edition of the Ordnance Survey Map, 1839, and in a number of other sources from the late 18th and early 19th cents. is Clare; the latter form, which is the name of the townland which gave its name to the town, appears in Hib. Del., 1685, and also in the records of the sale of Forfeited Estates, 1703.
There is some evidence, however, that despite the general use of Clare as an abbreviated form of the name- the form Claremorris was regarded, from the 18th cent at least, as the ‘more correct’ form of the name.
The Irish of the name occurs of course in Raftery’s song ‘Cill Aodain’; a copy of the song in a manuscript dated 1835 has Clarr Chloinne Muiris, while the Namebook, 1838, has Clar Chlann Muiris and Clar Chlann Muiris na mBrigh 9i.e. of Brees, or ‘.Brize’. Pop.1841 2,256; 1851 1,562(+500 in workhouse); 1871 1,103;
Extract from: “MAYO - Aspects of its Heritage” by Bernard O’Hara. Published by kind permission of author.