Big government is characterized by its size, which is quantified in terms of budget or workforce count, either in absolute terms or concerning the broader country's economy.
Big government is a derogatory word for a government or public domain that is seen too large or active in some sectors of policymaking or the corporate sector in an unlawful manner.
Similar to the British term 'nanny state,' the word can also refer to government programs that aim to control issues that are deemed private or individual, including private sexual activity or individual dietary choices. In the United States, the word has also been used to describe a powerful federal government that wants to exert influence over local institutions, such as the overcoming of government authority in support of federal law.