design vs purpose

design

verb
  • To manifest requirements to be satisfied by an object or process for them to solve a problem. 

  • To plan and carry out (a picture, work of art, construction etc.). 

noun
  • A plan (with more or less detail) for the structure and functions of an artifact, building or system. 

  • A pattern, as an element of a work of art or architecture. 

  • The art of designing 

  • The shape or appearance given to an object, especially one that is intended to make it more attractive. 

  • The composition of a work of art. 

  • Malicious or malevolent intention. 

  • A specification of an object or process, referring to requirements to be satisfied and thus conditions to be met for them to solve a problem. 

  • Intention or plot. 

purpose

verb
  • To have or set as one's purpose or aim; resolve to accomplish; intend; plan. 

  • To have (an) intention, purpose, or design; to intend; to mean. 

noun
  • meaning for existing or doing something. 

  • Resolution; determination. 

  • Function, role. 

  • The end for which something is done, is made or exists. 

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