When it comes to finding synonyms for the phrase "hammered in," there are many options available. For instance, if you want to express the idea of something being firmly and forcefully established, you might choose words like "set in," "cemented," or "anchored." Alternatively, you could use phrases such as "driven home," "locked in," or "pressed down" to convey a similar sense of permanence and strength. Other options might include terms like "reinforced," "strengthened," or "fortified," each of which emphasizes the notion of something being made more secure or resilient. Ultimately, the precise synonym you choose will depend on the specific context and connotations you want to convey, and on the tone and style of your writing.