achievement vs act

achievement

noun
  • The act of achieving or performing; a successful performance; accomplishment. 

  • A great or heroic deed or feat; something accomplished by valor or boldness. 

  • The lexical aspect (aktionsart) of verbs or predicates that change in an instant. 

  • An award for completing a particular task or meeting an objective in a video game. 

  • An escutcheon or ensign armorial; a full display or depiction of all the heraldic components to which the bearer of a coat of arms is entitled; (now especially) a funeral shield: the hatchment. 

  • The successful completion of a socially defined goal or task, highlighting individual or group accomplishment. 

act

noun
  • The process of doing something. 

  • A product of a legislative body, a statute. 

  • A display of behaviour. 

  • A display of behaviour meant to deceive. 

  • A division of a theatrical performance. 

  • Something done once and for all, as distinguished from a work. 

  • Any organized activity. 

  • A performer or performers in a show. 

  • A formal or official record of something done. 

  • A thesis maintained in public, in some English universities, by a candidate for a degree, or to show the proficiency of a student. 

  • Something done, a deed. 

verb
  • Of a play: to be acted out (well or badly). 

  • To perform a theatrical role. 

  • To play (a role). 

  • To convey an appearance of being. 

  • To map via a homomorphism to a group of automorphisms (of). 

  • To feign. 

  • To do something. 

  • To have an effect (on). 

  • To behave in a certain manner for an indefinite length of time. 

  • To do something that causes a change binding on the doer. 

How often have the words achievement and act occurred in a corpus of books? (source: Google Ngram Viewer )