| falling-off(decline, deterioration, degeneration) |
| falloff(decline, deterioration, degeneration) |
| feeble |
| fizzle out(verb, expression, suffer, fade, faint) |
| fluidify(verb, run, soften, dissolve, melt) |
| flux(verb, run, soften, dissolve, melt) |
| fracturing(adjective, decaying, crumbling, pooped) |
| fragile |
| fraying |
| fuse(verb, run, soften, dissolve, melt) |
| get worse(verb, expression, decline, degenerate, deteriorate) |
| getting worse(verb, expression, decline, molder, curdled) |
| gnawing away |
| go bad(verb, expression, decline, degenerate, deteriorate) |
| go downhill(verb, expression, decline, stain, warp) |
| go soft(verb, expression, suffer, faint, dissolve) |
| go to pot(verb, expression, idiom, decline, stain) |
| go to seed(verb, expression, idiom, degenerate, deteriorate) |
| go to the dogs(verb, expression, idiom, decline, degenerate) |
| going bad(verb, expression, decline, molder, curdled) |