In Common Usage. emphases is one of the 10000 most commonly used words in the Collins dictionary.
structure. n. 1. a complex construction or entity. 2. the arrangement and interrelationship of parts in a construction, such as a building. 3. the manner of construction or organization: the structure of society.
My formal (but open to improvement) definition of 'science': A science is a method, a set of rules using fact and logic, for evidence gathering and testing truth claims in a given field of inquiry, rules which are publicly usable (i.e., neutrally applied to all participants), and which can reasonably be said to lead to the truth of that particular area.