| inclination(drop, decline, fall, plunge, slide) |
| incline(drop, fall, plunge, slide, dive) |
| kink |
| landslide(drop, decline, fall, plunge, slide) |
| lapse(noun, failure) |
| malfunction(noun, failure) |
| nosedive(noun, fall, spin, dive, spiral) |
| plummeting(drop, decline, fall, plunge, slide) |
| plunge(noun, drop, decline, fall, slide) |
| plunging(drop, decline, fall, plunge, slide) |
| pratfall |
| precipitation(drop, decline, fall, plunge, slide) |
| prolapse(noun, drop, decline, fall, collapse) |
| sag(drop, fall, stoop, dive, ebb) |
| settlement(drop, decline, fall, plunge, slide) |
| sinkage(noun, drop, decline, fall, collapse) |
| sinking(drop, decline, fall, plunge, slide) |
| slant(noun, drop, decline, fall, collapse) |
| slide(drop, fall, plunge, dive) |
| slip(drop, fall, plunge, slide, dive) |