Monarch is....... n.
Buckingham Palace.
"Manarch" is a portmanteau of "man" and "anarchist" which refers to a man who espouses anarchist beliefs but behaves in a patriarchal or oppressive manner, contradicting the principles of equality and liberation that anarchism advocates for.
I think the word you are asking about is monarch. A monarch was a sole head of a government, whose position was hereditary to at least some degree. A king was a monarch, as was an emperor. There were princes, dukes, and even counts who were monarchs, because they did not have royal overlords, but were at the top of their governments.
An absolute monarchy is a government in which the ruler holds absolute power over his country. Many absolute monarchs from the past believed that they had a divine right to power from God, and that therefore limits should not be placed upon their power.
Monarchs is another word for kings. Today's kings no longer do any actual ruling. They have the formal role of "Head of State' and their activities are largely ceremonial, like opening the sessions of Parliament, receiving ambassadors and signing laws. Many hold high army, navy and air force ranks but these are also ceremonial: a king is never expected to do any actual fighting. In many countries they have a much more important symbolic role: they embody the continuity and unity of their country and by their presence at certain functions give a signal which activities in the eyes of the Government are important and deserve recognition.