new word

Even by age 1, many infants seem to think that if they hear a new word, it means something different from the words they already know.

The new insight stands in contrast to a prior explanation for how children build vocabulary: that they rely on the concept of "mutual exclusivity," meaning they treat each new word as corresponding to a new object or category.

What Aravind, Brody, and Fieman propose is that children have no such tendency, and instead rely on so-called "focus" signals to decide what a new word means.

If a new word was said without focus, children thought the word meant the previously named object 71 percent of the time.

But when hearing the new word spoken with focus, they thought it must refer to a new object 87 percent of the time.