The word "de-materializes" refers to something disappearing or becoming insubstantial. Antonyms for this word would be terms that suggest something becoming material or solid. Examples of such antonyms might include "solidifies," "materializes," "condenses," or "coagulates." These terms imply a process of substance or matter being created or coming into being, as opposed to vanishing or dissolving. Other possible antonyms for "de-materializes" might be "forms," "transforms," or "consolidates," all of which suggest a process of building or accumulating rather than disappearing. Ultimately, the antonyms for "de-materializes" are words that suggest the opposite of something fading away or losing substance, instead implying a process of growth or consolidation.