Manage to remember something, or to feel or express an emotion, with difficulty. "Robertson tried to dredge up an image of her in his mind.", "From somewhere she dredged up a brilliant smile."
Start talking again about something that happened a long time ago, especially something unpleasant. "Newsweek magazine dredged up some remarks which he made last year."
If someone dredges up a piece of information they learned a long time ago, or if they dredge up a distant memory, they manage to remember it. an American trying to dredge up some French or German learned in high school
If someone dredges up a damaging or upsetting fact about your past, they remind you of it or tell other people about it. I wouldn't want to dredge up the past It's the media who keep dredging it up