blue streak noun2 •(informal) A great deal of fast talking, cursing, lying, or similar.interspersing his vehement comments with a ‘blue streak’ of oaths — 1847 •A trace left by something that is too quick to see.An American engineer, who had been in England, described the Express train from Liverpool to London as running a "blue streak," by which he meant going like lightning. — 1867
