Definition of ideal
- ideal Adjective Optimal; being the best possibility.
- ideal Adjective Perfect, flawless, having no defects.
- ideal Adjective Existing only in the mind; conceptual, imaginary.
- ideal Adjective Not actually present, but considered as present when limits at infinity are included.
- ideal Noun A perfect standard of beauty, intellect etc., or a standard of excellence to aim at.
- ideal Noun A subset of a partially ordered set comprising an element and all elements less than it.
- ideal Noun A subring closed under multiplication by its containing ring.