pentarchy

As nouns the difference between oligarch and pentarchy

is that oligarch is a member of an oligarchy, someone who is part of a small group that runs a country while pentarchy is government by five persons.

Oligraphy is likely misspelled.

Oligraphy has no English definition.

As a noun pentarchy is

government by five persons.

As nouns the difference between oligarchy and pentarchy

is that oligarchy is a government run by only a few, often the wealthy while pentarchy is government by five persons.

Pentarchic is a derived term of pentarchy.

As an adjective pentarchic

is relating to a pentarchy.

As a noun pentarchy is

government by five persons.

As nouns the difference between nation and pentarchy

is that nation is (label) nation while pentarchy is government by five persons.

As nouns the difference between federation and pentarchy

is that federation is act of joining together into a single political entity while pentarchy is government by five persons.

As an adjective federation

is of an architectural style popular around the time of federation.