accusant
accuser
allegator
appellant
bellyacher
claimant
complainer
crab
crank
croaker
delator
faultfinder
frondeur
griper
grouch
grouser
growler
grumbler
impeacher
impugner
indictor
informer
kicker
kvetch
libelant
malcontent
murmurer
mutterer
party
petitioner
plaintiff
prosecutor
querulous person
reactionary
reactionist
rebel
sorehead
suitor
the prosecution
whiner
litigant
litigator
suer
breach of promise
brickbat
confrere
cowbird
defendant
depositary
entryman
firesetter
informant
juror
juryman
law-and-order
mortician
ordinariness
procureur
superbeing
traducer
unsuccess