monoid

1 9.9

A set with a rule to combine items where grouping does not matter and one item never changes others

noun
/ˈmoʊnɔɪd/

Specialized

: monoide

A monoid can be easily demonstrated using strings, where concatenation serves as the operation and the empty string is the identity.

Examples

So here's for example how I could define a some monoid I inherit from the base with int, for example here.
In programming, a monoid combines a set with an associative operation and an identity element.
When performing calculations in algebra, a monoid is essential for understanding how different elements interact under a given operation.

Surface Forms

monoid singular

monoids plural

Morphology

monoid = mon + oid

Although the word contains the classical elements mon- and -oid, the mathematical sense is a specialized technical coinage not directly predictable for most learners from those parts alone.

Etymology

The word monoid comes from the Greek parts mono- 'single' and -oid 'form' or 'like'. In math, a monoid is a set with one main way to combine elements and an identity element that 'does nothing' when you combine it, so the name reminds you of a single-form system with one operation.