1. descend, fall, go down, come down, travel, go, move, locomote
usage: move downward and lower, but not necessarily all the way; "The temperature is going down"; "The barometer is falling"; "The curtain fell on the diva"; "Her hand went up and then fell again"
2. reduce, come down, boil down, become, turn
usage: be the essential element; "The proposal boils down to a compromise"
3. precipitate, come down, fall
usage: fall from clouds; "rain, snow and sleet were falling"; "Vesuvius precipitated its fiery, destructive rage on Herculaneum"
4. sicken, come down, worsen, decline
usage: get sick; "She fell sick last Friday, and now she is in the hospital"
5. come down, knock, criticize, criticise, pick apart
usage: criticize or reprimand harshly; "The critics came down hard on the new play"