kalendae

The Kalends (Latin k/calendæ, -arum), (or calends) correspond to the first days of each month of the Roman calendar. This term can be traced back to the Etruscans, which could explain the appearance of the letter k, a letter less favoured by Latin than the letter c (the few Latin words containing a k are often borrowed from the Etruscans). Another explanation of the word's roots is that it is from the Latin language: from the word calendae (the called), from the infinitive calare (to call).
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calendae.

N F
Kalends (pl.)| 1st of month; abb. Kal./Kl.; day of proclamation| interest due