# MemberOf Relation

A MemberOf Relation is a strict partial order binary relation between a thing (the member) an another thing.

**AKA:**∈, Member Of Relation, In, Membership, Element Of.**Context:**- It can be a:
- It can be read as "[math]x[/math]
*is a member of set*[math]X[/math]". - It can be written as: "[math]x \in X[/math]"

**Example(s):**- Set Member Relation, such as an Is A Type Of Relation (between a subclass concept and a superclass concept).
- Multiset Member Relation, such as between a Multiset Member and a Multiset.
- Sequence Member Relation, such as between a Sequence Member and a Sequence.
- String Member Relation, such as between a String Member and a string.
- Tuple Member Relation, such as between a Tuple Member and a Tuple.

**See:**Non-Member Relation, Subset Relation, IsA Relation.