It’s an amusing exercise, though native English speakers don’t often need things explained to them with the 1,000 most common words because, as pointed out above, even quite young people already know a great deal more more than that.
It’s more relevant for ESL students (English as a Second Language) who may be well educated adults in their own language, with very limited English vocabulary. Here we have the example of the Oxford Advanced Learner’s Dictionary, in which all the definitions are composed using the Oxford 3000 wordlist, which is the 3,000 most useful English words to know if you are a foreign student. You might not know the Oxford 3000, but you can look them up because they’re in the dictionary.
