| be impaired(decline, weaken, lessen, degenerate, deteriorate) |
| become contaminated(expression, decline, weaken, lessen, degenerate) |
| blight(verb, decline, weaken, lessen, degenerate) |
| collapse(decline, weaken, lessen, degenerate, deteriorate) |
| corrode(verb, decline, weaken, lessen, degenerate) |
| curdle(verb, decline, weaken, lessen, degenerate) |
| decline(weaken, lessen, degenerate, deteriorate, wane) |
| defile(verb, decline, weaken, lessen, degenerate) |
| degenerate(verb, decline, weaken, lessen, deteriorate) |
| depreciate(decline, weaken, lessen, degenerate, deteriorate) |
| deteriorate(verb, decline, weaken, lessen, degenerate) |
| discolor(verb, decline, weaken, lessen, degenerate) |
| dissolve(verb, decline, weaken, lessen, degenerate) |
| dry-rot(decline, weaken, lessen, degenerate, deteriorate) |
| dwindle(decline, weaken, lessen, degenerate, deteriorate) |
| fade(verb, decline, weaken, lessen, degenerate) |
| fail(decline, weaken, lessen, degenerate, deteriorate) |
| gather |
| get worse(expression, decline, weaken, lessen, degenerate) |
| go to seed(expression, idiom, decline, weaken, lessen) |