“It’s not hard to find sage quotes about words. It’s much harder to define them. … How is it that words can be so common, so fundamental, yet so elusive? A key discovery is that words are not just a sound pattern (cat, gato, neko) and a meaning (furry-domesticated-meows), but also contain something in between, a kind of “middle word,” which psycholinguists refer to as a lemma. The name comes from mathematics, where it refers to an intermediate step in a theorem. You can think of word lemmas as the hidden network that computes the translation between word sound and word meaning. How do we know lemmas exist? There are several bits of evidence, including computational arguments, neural network simulations, and behavioral studies showing that when people get themselves into tip-of-the-tongue states—a failure to access the sound pattern of a word—they know more about the word than just its meaning, such as fragments of its syntactic properties. There’s another fascinating source of evidence, though: neurological cases in which people appear to have lost their middle-word realm altogether.”

Read in full: https://www.psychologytoday.com/us/blog/wired-for-words/202508/the-secret-life-of-words