'Yama' is God of death and 'damshtra' means his tooth. It's applied meaning is the period of increased mortality.
The duration of last eight days of Kartika month and first eight days of Margashirsha month is termed as yamadamshtra.
It is advised to take little food during this period for healthy living otherwise it may be fatal.
- ↑ Sharangadhar Purva khanda 2/30