mid 17th century: modern Latin, from Greek para- 'beside' + metron 'measure'
Until recently, use of the word parameter was confined to mathematics and related technical fields. Since around the mid 20th century, however, it has been used in nontechnical fields as a technical-sounding word for ‘a limit or boundary,’ as in they set the parameters of the debate. This use, probably influenced by the word perimeter, has been criticized for being a weakening of the technical sense. Careful writers will leave parameter to specialists in mathematics, computer science, and other technical disciplines. As a loose synonym for limit, boundary, guideline, framework, it is a vogue word that blurs more than it clarifies. Perimeter is a different word, meaning ‘border, outer boundary, or the length of such a boundary.’.