What is the meaning of Hearsay?

Information that was heard by one person about another that cannot be adequately substantiated.

Evidence based on the reports of others, which is normally inadmissible because it was not made under oath, rather than on personal knowledge.

An out-of-court statement offered in court to prove the truth of the matter asserted (or the in-court testimony which recites such a statement), which is normally inadmissible (because it is not subject to cross-examination) unless it falls under one of a number of exceptions.

Source: wiktionary.org