Thinking that moves away in diverging directions so as to involve a variety of aspects and which sometimes lead to novel ideas and solutions; associated with creativity(noun)
WordNet. Princeton University. 2010.
Use "out-of-the-box thinking" in a sentence
"Early on, the precedent was established permitting the stringing-together of several words: the going-out-of-business sale of the Depression is matched in word number by out-of-the-box thinking today."