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.
Technically, science means the systematic study of the structure and behavior of the physical and natural world. Political science attempts to claim the rubric of science because of its systematic study of politics (as opposed to the physical and natural world; i.e., the modifier political.).