Lexis

Thus, alongside current lexis, words and senses now obsolete find a place in a dictionary on historical principles.

By the 1980s, English language teachers generally had begun to realize that there had been a neglect of lexis in teaching methods and coursebooks. […] The basic truth that without vocabulary or lexis we can't express anything had to be restated and a new approach to teaching lexis was needed.

In this broadsheet newspaper, the reporter uses a complicated and formal lexis which I find hard to understand.