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How many words are in the English language?
There are about a million English words, maybe more. It is hard to see how even a conservative estimate of English vocabulary could go much below a million words. If you allow all of scientific nomenclature, this could easily double the figure. For example, there are apparently some one million insects already described, with several million more awaiting description. The two largest dictionaries - the Oxford English Dictionary and Merriam-Webster's Third New International Dictionary - each include around half a million words (or lexemes).