The phrase "renders solid" implies something that has been made stable, firm or strong. In contrast, some antonyms to this phrase might include terms such as weakens, destabilizes, or undermines. For instance, when an object becomes fragile or frail, it is the opposite of rendering solid. Similarly, when emotional distress or anxiety starts to unravel our mental stability, it can be considered an antonym of rendering solid. Overall, antonyms for the phrase "renders solid" represent the characteristics of something that has been made unstable, fragile or weakened.