Definition of "whereby"

whereby

/wɛə(ɹ)ˈbaɪ/

adverb
not comparable
1. (interrogative, obsolete) By what, in which direction; how.
2. By which.
  Quotations
  Shylock:Nay, take my life and all; pardon not that:You take my house when you do take the propThat doth sustain my house; you take my lifeWhen you do take the means whereby I live.
  c. 1596–1598 (date written), William Shakespeare, “The Merchant of Venice”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, [Act IV, scene i]
  Other heads saw devolution as a whole new way of life and adopted an approach whereby the power of devolution was used to enable the school to drive the curriculum.
  1990, Local management of schools, Kogan Page Ltd
3. (nonstandard) Where, wherein, in which.