Solemnify is a word used to describe the act of making something serious, grave, or solemn. When it comes to expressing a similar idea, some of the synonyms for solemnify include solemnize, sanctify, consecrate, hallow, and dignify. Solemnize is a term that refers to creating an atmosphere of reverence or seriousness, often in religious rituals or ceremonies. Sanctify, on the other hand, implies the idea of making something sacred or holy. Consecrate is another synonym for solemnify, which means to devote something to a sacred purpose. Hallow is another word that has a similar meaning to solemnify, which refers to honoring something as sacred or holy. Finally, dignify is a term that suggests elevating something to a higher level of respect or importance.