lunar year 
noun
A period of twelve lunar months (approximately 354 days).It may be useful to note, first of all, that the Muslim year is a lunar year of twelve months, that is, about ten days short of a solar year....
- In marking off days and lunations on lengths of dowel, the eleven day disparity between the solar year and the lunar year is found directly.
- The lunar year is approximately 354 days long, so the months rotate backward through the seasons and are not fixed to the Gregorian calendar.