ませる(すませる) To finish homework, chores. “No dessert until you finish your spinach!”
(かんせい) To complete – usually said of a painting, construction of a building, or other physically creative project.
(かんりょう) To finish work on a project – an annual report, a re-formatting of the database, etc.
 (しゅうりょう) Something (a contract, a subscription, a statue of limitations) expires or terminates.
(けつまつ) The conclusion of something – the last chapter of a book or the last scene of a movie.
わり(おわり) “The end” – usually written at the end of old movies. Also said out loud by someone who wants to declare victory and change the subject.
(かんぜん) Perfect, as in ‘the perfect crime’ or ‘perfectly safe.’ Also, perfect as in, ‘My new project is perfectly complete, now the finishing touches are over.’