Sentence:  My story started on a <WSD>calendar day</WSD> — July 2nd,1977 — and ended on a <WSD>calendar day</WSD> — February 14th, 1978 — but in between there was no calendar. 
Meaning of the word marked with <WSD> tags:  A day having a conventional designation on a recognized calendar, such as a numerical identification within a named month.