Definitions for "CALENDAR QUARTER"
The period of three consecutive calendar months ending March 31, June 30, September 30, and December 31.
The 3 month period beginning with January, April, July, and October. 1st quarter: January 1 through March 31 2nd quarter: April 1 through June 30 3rd quarter: July 1 through September 30 4th quarter: October 1 through December 31
The three-month period beginning on the first day of January, April, July and October each year and ending on the last day of March, June, September and December, respectively.
Keywords:  month, three, period
a three-month period