quincena

Etymology
From.

Noun

 * 1)  a period of fifteen days
 * 2)  a half month period, specially applied for wage payment
 * 3)  wage payment amount (in a half month period)

Usage notes

 * For wage periods, it may begin from first day to 15th of month, called primera ("first"), or from 16th to last day of month, called segunda ("second").
 * Second half of months having 31, and of February, are also called quincena, in spite of not having 15 days.