interpunct

An interpunct · is a small dot used for interword separation in ancient Latin script, being perhaps the first consistent visual representation of word boundaries in written language. The dot is vertically centered, e.g. "DONA·EIS·REQUIEM", and is therefore also called a middle dot or centered dot. In addition to the round dot form, inscriptions sometimes use a small equilateral triangle for the interpunct, pointing either up or down. Such triangles can be found on inscriptions on buildings in the twentieth century. Ancient Greek, by contrast, had not developed interpuncts; all the letters ran together. When a wave of enthusiasm for all things Greek swept ancient Rome, the use of interpuncts disappeared, presumably being inadequately fashionable. The use of spaces for word separation didn't appear until much later, some time between 600 and 800 AD.
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