An achievement is something which someone has succeeded in doing, especially after a lot of effort. Reaching this agreement so quickly was a great achievement = accomplishment
The act of achieving or performing; an obtaining by exertion; successful performance; accomplishment; as, the achievement of his object
Achievement is the process of achieving something. Only the achievement of these goals will bring lasting peace
An escutcheon or ensign armorial; now generally applied to the funeral shield commonly called hatchment