1) Date for Calpurnia 2) Roman date 
• (n. pl.) The first day of each month in the ancient Roman calendar.
The first day of the month, which belonged to Janus. Also spelt kalends. Derivation of the word calendar. 
Cal'ends noun plural [ Middle English kalendes month, calends, Anglo-Saxon calend month, from Latin calendae ; akin to calare to call, proclaim, Greek ................... CF. Claim .] The first day of each month in the ancient Roman calendar. [ Written also kalend...
Calends was the first day of the Roman calendar month.
calends From calare, 'to call'. The first day of the Roman month. Varro said the term was first used to call the people together on the first day of the month when the pontifex told them of the time of the new moon, the day of the nones, and the festivals and sacred days to be observed. The custom continued until A.U.C. 450 when the fasti or calen...