[Ylpertnodi]

...not convinced 'fortnight' is actually imperial (as opposed to just old):

https://www.merriam-webster.com/dictionary/fortnight Middle English fourtenight, alteration of fourtene night, from Old English fēowertȳne niht fourteen nights.

(First Known Use of silver lining - 1871, same source) ...and as for etc (Et cetera), may I offer you my contrafibularities.

[KineticLensman]

Yes, I wasn't being totally serious. Pro-metric people sometimes jokingly refer to the 'imperial' 3F system by analogy with the SI system and others.

I think 'Fortnight' is rapidly falling out of use in British English. I would be much more likely to say 'a couple of weeks'