Alphabet Anatomy intentionally uses “big words” to describe each letter’s life and character, and there are even a few not so common words in Meet the Capital Letters’ rhyming verses. There seems to be some controversy that preschool children may find these words “over their heads” or that “big words” may not be suitable to use in teaching and/or reading with these younger children. Not true. In fact, research has shown that young children are very capable of comprehending new, and not so common, words when given that opportunity.
Young children love the sound of long and seemingly difficult words. Your child might suddenly blurt out that her friend’s behavior is “ridiculous” or that the baby’s diaper is “saturated.” These instances of surprisingly sophisticated language use come from children’s attention to, and interest in, the way adults use words to express precise feelings and reactions. So don’t shy away from using words you think are over your child’s head; instead, use them as part of your natural conversation and children will gradually pick up on their meanings.” http://www.scholastic.com/browse/article.jsp?id=8100
So bring on the “big words.” Your child will benefit immensely from a rich, deep, and diverse vocabulary!