The tenth month of the year, as it was known to the Men and Hobbits of Bree. In the Shire, the name was slightly different, and it was known there as Winterfilth. It was derived ultimately from the Elvish name for the month, Narquelië, 'fading of the Sun' - that is, the onset of winter.
Notes
1
Wintring was by no means the most 'wintry' of months on the Bree calendar (that would have been Yulemath or Frery, approximately December or January on a modern calendar). In context, the name must have meant something like the 'coming of winter', so Wintring marked the beginning of the colder months of the year, rather than the most 'wintry'.