Real Dictionary

god
proper noun: The name God is given to the spirit or being who is worshipped as the creator and ruler of the world, especially by Jews, Christians, and Muslims.

god in American English
any of various beings conceived of as supernatural, immortal, and having special powers over the lives and affairs of people and the course of nature; deity, esp. a male deity: typically considered objects of worship
used variously, and in interjectional phrases, as an oath and as an expression of relief, determination, surprise, anger, etc.
interjection: (used to express disappointment, disbelief, weariness, frustration, annoyance, or the like)
noun: the one Supreme Being, the creator and ruler of the universe
transitive verb: to regard or treat as a god; deify; idolize

God in British English
noun: a supernatural being, who is worshipped as the controller of some part of the universe or some aspect of life in the world or is the personification of some force
noun: the sole Supreme Being, eternal, spiritual, and transcendent, who is the Creator and ruler of all and is infinite in all attributes; the object of worship in monotheistic religions