 Citations from the late 19th century, however, show the phrase describing horses having the stamina to remain on the course of a racetrack.Safire found the same, writing that the earliest such use found was for an 1873 rowing competition.Safire's correspondent, lexicographer Benjamin Zimmer, pointed out that before that, "citations for 'stay the course' invariably have the countervailing sense of 'to stop or check the course (of something).'"