sennight

noun

1. (archaic, obsolete, poetic)Synonym of week in its various senses, a period of seven consecutive days and nights.

   “I dranke not this sennet A draught to my pay; Elynour, I thé pray, Of thyne ale let vs assay, […]”

   “Marry he trots hard vvith a yong maid, betvveen the contract of her marriage, and the day it is ſolemnizd: if the interim be but a ſennight, Times pace is ſo hard, that it ſeemes the length of ſeuen yeare.”

   “And Mrs. Jevvkes tells me, every one names Thurſday come Sev'nnight for our Nuptials.”

   “Sir Robert Pringle and John Hunter attended the meeting of Heritors intimated here on Sunday gone a se'enight.”

   “We leave Bath, as she has perhaps told you, on Saturday se'nnight.”