Antonyms for the phrase "fling off" include "retain," "hold," "grasp," "clutch," and "embrace." These antonyms suggest a sense of control and restraint, rather than a sudden, violent release. Retaining something implies a sense of ownership, whereas flinging something off suggests abandonment or rejection. Grasping, clutching, and embracing all suggest a holding on, rather than a letting go. In contrast, flinging off implies a sense of recklessness or impulsivity, as if one is throwing caution to the wind. By considering these antonyms, we can better understand the nuances of the phrase "fling off" and its implications for the actions and emotions it suggests.