The most common use of the word "wonder" these days is to express a question in a way that isn't likely to be answered, as in "I wonder when this tree will blossom?" It's also used to play with very young children with peek-a-boo games. "I wonder where Holly is? Where could she be? There she is!"
The deeper meaning of the word is what makes things wonderful. Full of wonder. Some adults are afraid of "wonder," though, because it involves relaxing into not understanding. It requires acceptance that one does not know. At its core, it is acceptance of and admiration for the mysterious and the hidden. It is taking joy in the revelation of simple things for which there are no words.
Similar page, SandraDodd.com/wonder
(though the quote is from page 279 (or 322) of The Big Book of Unschooling)
photo by Sandra Dodd
__