Over-the-top describes remarks or behaviour that go so far they seem silly, fake, rude or just too much — thanks so huge they sound empty, anger so big it looks like a show, clothes or film effects so loud they stop being fun. It is informal. British speakers often shorten it to OTT. You can say the speech was over-the-top, or that someone went over the top. Though actually, the phrase had a harder life first: in the First World War, to go over the top was to climb out of the trench and run toward the enemy — a terrible, extreme act. The everyday meaning kept the picture of going past a sensible line, even though most people who say it now are not thinking of the war at all. It is not a compliment, and it does not mean “the best.”