Dr. Castro's publication on The Conversation
The days of having a dictionary on your bookshelf are numbered. But that’s OK, because everyone already walks around with a dictionary – not the one on your phone, but the one in your head.
Just like a physical dictionary, your mental dictionary contains information about words. This includes the letters, sounds and meaning, or semantics, of words, as well as information about parts of speech and how you can fit words together to form grammatical sentences. Your mental dictionary is also like a thesaurus. It can help you connect words and see how they might be similar in meaning, sound or spelling.
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