inform

What it means

1. archaictransitiveTo instruct, train (usually in matters of knowledge).
2. transitiveTo communicate knowledge to.

   I am informed thoroughly of the cause.

   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, →OCLC, [Act IV, scene i]

   1 more example

   For he would learn their business secretly, / And then inform his master hastily.

   1591, Ed[mund] Sp[enser], “Prosopopoia. Or Mother Hubberds Tale.”, in Complaints. Containing Sundrie Small Poemes of the Worlds Vanitie. […], London: […] William Ponsonbie, […], →OCLC

   Synonyms: acquaint

3. intransitiveTo impart information or knowledge.

In a sentence

For he would learn their business secretly, / And then inform his master hastily.

1591, Ed[mund] Sp[enser], “Prosopopoia. Or Mother Hubberds Tale.”, in Complaints. Containing Sundrie Small Poemes of the Worlds Vanitie. […], London: […] William Ponsonbie, […], →OCLC

Where it comes from

1. Latinīnfōrmō“to shape, form, train, instruct, educate”
2. Old Frenchenformer
3. Middle Englishinformen
4. Englishinform

From Middle English informen, enformen, borrowed from Old French enformer, informer (“to train, instruct, inform”), from Latin īnfōrmō (“to shape, form, train, instruct, educate”), from in- (“into”) + fōrma (“form, shape”), equivalent to in- + form.