OED::

The September 2017 quarterly update of the Oxford English Dictionary includes more than 1,000 new headwords, senses, and subentries. The full list of new entries can be found here.

Not all words that are new to the dictionary are new in the sense of being recent additions to the English language itself. Many additions are ancient and obsolete, but they contribute to the OED’s mission of recording the millennium-long history of English. One evocative obsolete word in the new update is the verb afound meaning ‘to become numb or stiff with cold’, an Anglo-Norman loanword used by Chaucer. Another is through-smite (‘to pierce or run through, as with a spear or other pointed weapon’), which was used by John Gower and William Caxton, among others. By the 19th century, through-smite was only in self-consciously poetic or archaic use, and by the early 20th century it had fallen out of use altogether.