Crystallize vs Undefined - What's the difference?

As a verb crystallize

is (transitive|chemistry|physics) to make something form into crystals.

lacking a definition or value.

* crystalize * (non-Oxford British spelling) crystallise, crystalise

(crystalliz)

(transitive, chemistry, physics) to make something form into crystals

I crystallized the copper sulphate by slowly cooling a saturated solution.

to assume a crystalline form

The copper sulphate crystallized from solution.

to give something a definite or precise form

After some thought, I crystallized my ideas for the paper.

to take a definite form

My ideas crystallized overnight.

to coat something with crystals, especially with sugar

We crystallized the fruit by coating in sugar.

* crystallizable * crystallization / crystallisation

(wikipedia undefined) (-)

Lacking a definition or value.

(mathematics, computing) That does not have a meaning and is thus not assigned an interpretation.

The result of division by zero is undefined .

* defined