The word “hiatus”, which is borrowed directly from Latin, originally meant a gap or opening. That is, a physical gap, like a hole or even a chasm or canyon. That’s how Richard Burthogge used it in 1675: “He saw two Openings or Hiatus in the Earth.” Even Ben Franklin used it, in the December 15th edition of his Pennsylvania Gazette in 1737: “These Hiatus’s at the Bottom of the Sea, whereby the Abyss below opens into it and communicates with it.”
The Pennsylvania Gazette, if it still exists, probably isn’t quite the same as it was in Franklin’s time. The article quoted above was about the causes of earthquakes. Not exactly breaking news, but at least shaking news.
“Hiatus” was adopted as a medical term in the late 1800s, when it began to be used to describe a “hiatus hernia,” or more recently, “hiatal hernia.” It has also been used to refer to rips in clothes, as Laurence Sterne did when he wrote “Tristram Shandy” in 1761: “The hiatus in Phutatorius’s breeches was sufficiently wide to receive the chesnut.”
The meaning of “hiatus” as an interruption in a chronological sequence has been around since the 1600s, and now is the only way “hiatus” is still in common use. Its meaning is exactly the same now as it was in 1844 when Henry Rogers wrote “In 1671..there is another hiatus in his correspondence. It extends over three years.” He was talking about contributions to the Edinburgh Review. Since Rogers apparently knew the “correspondence” resumed around 1674, but unfortunately it’s not clear nowadays what he was talking abut. There’s been too big a hiatus in anyone paying attention to it.