"Deeply felt" refers to intense emotions that are strongly experienced by an individual. It can also describe opinions or beliefs that are held passionately and with great conviction. Synonyms for "deeply felt" can include passionately held, fervently believed, profoundly experienced, intensely realized, and strongly sensed. Other options might include passionately held views, fervent conviction, deeply ingrained beliefs, and keenly felt emotions. These phrases all indicate a strong, unwavering sense of something that is deeply intertwined with an individual's personal experiences and beliefs. Using a variety of synonyms can help to add nuance and depth to your writing, as well as convey the intensity of your emotions or convictions.