Report, rumor, gossip, hearsay are comparable when they mean common talk or an instance of it that spreads rapidly.
Report is the most general and least explicit of these terms; it need not imply an authentic basis for the common talk, but it often suggests some ground for the belief unless specifically qualified (as by false, untrue, or wild).
Rumor applies to a report that flies about, often gains in detail as it spreads, but lacks both an evident source and clear-cut evidence of its truth.
Gossip applies to idle talk, chiefly about personal affairs and behavior, that is the source of or means of propagating rumors or reports, and is sometimes used in the sense of a rumor or report.
Hearsay carries a strong implication of the means by which a report or rumor comes to one, that is, by hearing rather than by seeing or knowing directly.
It is sometimes extended to a report or rumor based upon such hearsay.