The difference between Plurality and Simple majority

When used as nouns, plurality means the state of being plural, whereas simple majority means a plurality.

check bellow for the other definitions of Plurality and Simple majority

Plurality as a noun (uncountable):

The state of being plural.
Plurality as a noun (ecclesiastical):

The holding of multiple benefices.
Plurality as a noun (countable):

A state of being numerous.
Plurality as a noun (countable):

A number or part of a whole which is greater than any other number or part, but not necessarily a majority.
Plurality as a noun (countable):

A number of votes for a single candidate or position which is greater than the number of votes gained by any other single candidate or position voted for, but which is less than a majority of valid votes cast.
Plurality as a noun (countable):

A margin by which a number exceeds another number, especially of votes.
Plurality as a noun (countable):

A group of many entities: a large number.

Examples:

"A plurality of ideas were put forth at the meeting, most of which were rejected out of hand."
Plurality as a noun (countable):

A group composed of more than one entity.
Plurality as a noun (of spouses):

Polygamy.

Simple majority as a noun (British):

A plurality; the most of any alternative.
Simple majority as a noun (North America):

A majority; more than half.