ideal; perfect model
General use as a noun or na-adjective for an ideal standard or perfect example. Often used in philosophical, artistic, or everyday contexts.
He pursues his ideal of perfection.
This design is very ideal.
Technical term in ring theory. A subset of a ring closed under addition and multiplication by ring elements.
I learned about ideals in the ring of integers.
Borrowed from German 'Ideal'. The mathematical sense was introduced in the 19th century by German mathematicians.