Grinding into is a phrase typically used to convey the forceful and persistent nature of a certain action. Some synonyms that can be used interchangeably with the phrase are: wearing down, eroding, corroding, chipping away, depreciating, debasing, and undermining. These words represent a gradual but steady process of deterioration or weakening, often referring to physical objects or ethical values. Other synonyms that suggest a more aggressive and abrupt action are: pulverizing, smashing, crushing, breaking, decimating, annihilating, and demolishing. These words convey a sense of power and destruction, usually applied to larger structures or oppressive forces. Overall, the synonyms for grinding into offer a range of nuances and connotations to convey different types of persistence and intensity in an action.