Definition of "etch"

etch¹

/ɛt͡ʃ/

verb
third-person singular simple present etches, present participle etching, simple past and past participle etched
1. To cut into a surface with an acid or other corrosive substance in order to make a pattern. Best known as a technique for creating printing plates, but also used for decoration on metal, and, in modern industry, to make circuit boards.
2. To engrave a surface.
3. (figuratively) To make a lasting impression.
4. To sketch; to delineate.
  Quotations
  There are many such empty terms to be found in some learned writers, to which they had recourse to etch out their system.
  a. 1705, John Locke, “Of the Conduct of the Understanding”, in Posthumous Works of Mr. John Locke: […], London: […] A[wnsham] and J[ohn] Churchill, […], published 1706

etch²

/ɛt͡ʃ/

noun
1. Obsolete form of eddish.
  Quotations
  Black Oats are commonly sown upon an Etch Crop, or on a Lay which they plow up in January, when the Earth is moist, taking care to turn the Turf well, and to lay it even and flat.
  1707, J[ohn] Mortimer, The Whole Art of Husbandry; or, The Way of Managing and Improving of Land. […], 2nd edition, London: […] J[ohn] H[umphreys] for H[enry] Mortlock […], and J[onathan] Robinson […], published 1708