What is the origin of 'sleep tight'?
Read moreOne of the mysteries of the English language finally explained.
noun
rareA specified period of seven years.
- ‘This septennium must designate something peculiar and different from the time following.’
- ‘In Wurtemburg the fall has been somewhat less striking, the mortality rates for the two septennia and for the year 1894 being 199, 107, and 104 respectively.’
Origin
Mid 19th century: from late Latin, from Latin septem ‘seven’ + annus ‘year’.
