KO
capstone
climax
clincher
conclusive argument
copestone
crown
crusher
cutter
death stroke
deathblow
end-all
ender
final stroke
final touch
finishing stroke
floorer
garmentmaker
garmentworker
kayo
kayo punch
knockdown argument
knockout
knockout blow
last dab
last stroke
last touch
needleworker
quietus
settle
settler
sockdolager
stitcher
stopper
automobile driver
race car
race driver
racer
racing car
achiever
expressman
grader
hairdryer
hewer
melter
needlewoman
netball
palletizer
play-off
scaler
tanner
tapster