SkyfireDict

out of the blue   (TTS Sound)

The adj out of the blue has 1 sense

• unanticipated, unforeseen, unlooked-for, out of the blue -- (not anticipated; "unanticipated and disconcerting lines of development"- H.W.Glidden; "unforeseen circumstances"; "a virtue unlooked-for in people so full of energy"; "like a bolt out of the blue")

The adv out of the blue has 1 sense

• unexpectedly, out of the blue -- (in a way that was not expected; "her brother showed up at the wedding out of the blue")