Yearly, hundreds of words are discarded by lexicographers from the dictionary to make way for new words. Lexicographers spend hours researching word usage, scanning publications and other communications, and may drop words that are no longer in use.
The process works in reverse too. The lexicographers also look out for words that make their way back in usage again and these words are re-entered in the dictionary. "Wheatgrass" was one of the words lost to us for many years before health-conscious eaters put it back in circulation.
The Oxford University Press has started an initiative called "Save the Words" to prevent the lesser-known English words from becoming extinct and re-include them in the dictionary.
The OUP is enlisting the help of all of us in saving the words. You adopt an endangered word (or words) through "Save the Words" and pledge to use it (or them) more often in daily conversations and written communication. A lexicographer, encountering the word again, may reinstate them in the dictionary.
For every word you adopt, "Save the Words" will send you a certificate (like those which dot this post). All you have to do, after adopting a word, is something like this on a regular basis:
My sad life misquemes me so much that I am always lugent and nothing can mulcible me which accounts for my vultuous countenance.
(Not bad for a first time effort? Eh?)