noun
(authorship) A dramatic device in which an earlier event is inserted into the normal chronological flow of a narrative.
(psychology) A vivid mental image of a past trauma or other sensation that the trauma is happening in the present, especially one that recurs.
A similar recurrence of the effects of a hallucinogenic drug.
The condition of the flame propagating down the hose of an oxy-fuel welding system.
(databases) A query that operates against data from an earlier time, before it was changed.
verb
(intransitive) To undergo a flashback; to experience a vivid mental image from the past.