I tried kill -9 698 but the process did not die.
$ ps -ef | grep chromium 502 698 811 0 0:01.24 ?? 0:07.28 /Users/lucius/chromium/src/xcodebuild/Debug/Chromium.app/Contents/MacOS/Chromium 502 854 732 0 0:00.00 ttys001 0:00.00 grep chromium $ kill -9 698 $ ps -ef | grep chromium 502 698 811 0 0:01.24 ?? 0:07.28 /Users/lucius/chromium/src/xcodebuild/Debug/Chromium.app/Contents/MacOS/Chromium 502 854 732 0 0:00.00 ttys001 0:00.00 grep chromium 

kill -15 ...and if that doesn't work thenkill -1 ...and if that doesn't work thenkill -9 ...?