Define Republican form of government and state its essential characteristic

A republican form of government is the government
of a
sovereign state headed by a Head of
State usually called a
President elected for a fixed term of
office. In a republican
government, Political sovereignty is vested in the people or
the electorates.

CHARACTERISTICS OF REPUBLICAN GOVERNMENT 

• A Republican form of government will
  normally have the following
  characteristics
• Popular
  Representation i.e. Popular Sovereignty.
•  Succession to
  office of the President or Head of state through election. 
• Periodic or Regular
  elections of Political leaders.
• Political Responsibility i.e.
  responsiveness and accountability of rulers to the people. 
• Constitutional
  limitations to the exercise of power by political leaders. Nigeria adopted a
  republican form of government in 1963
•  Fundamental human
  rights must be guaranteed. 
•  Freedom of the
  press. 
• Respect for Public
  opinion.