1. Third person plural present subjunctive or second person plural imperative form of 'cristalizar' - to form into crystals or to become solid and clear
They hope that the sugar will crystallize into rock candy.
Espera-se que o açúcar cristalizem em bala de açúcar.
2. To solidify, take shape, or become clearly defined (figurative)
Let the ideas crystallize before you present them.
Deixe as ideias cristalizem antes de apresentá-las.