Army
Part of speech: noun
Definition: A large, highly organized military force, concerned mainly with ground (rather than air – and naval) operations # used absolutely for that entire branch of the armed forces #: The army got a better share of this year's budget increase then navy and air force. # (often capitalized) within a vast military, a very large tactical contingent (e.g. a number of divisions) #: The Fourth Army suffered such losses that its remainders were merged into the Second Army, also deployed on the Western front. The governmental agency in charge of a state's army. A large group of people working toward the same purpose. A large group of social animals working toward the same purpose. Any multitude
Police
Part of speech: noun
Definition: An organisation granted the legal authority to enforce the law. See usage note.Members of the police force.(plural=police) A police officer
Part of speech: verb
Definition: To enforce the law and keep order among (a group).To patrol an area.