The rock itself is modest in scale, measuring roughly 1.7 metres long, 0.6 metres wide, and 0.2 metres deep, with its longest edge running parallel to the road. What makes it remarkable is not its size but those two cup marks, simple circular depressions ground into the stone surface, which are among the most widespread and least understood motifs in prehistoric art across Atlantic Europe.

Cup marks are found throughout Ireland, Britain, and beyond, carved during the Neolithic and Bronze Age periods, though their precise purpose remains a matter of ongoing debate among archaeologists. They appear on standing stones, burial monuments, and exposed bedrock alike, sometimes alone and sometimes in elaborate compositions alongside rings, channels, and other abstract forms. The Teeromoyle example is spare, just the two cups on an otherwise plain surface, but that plainness is itself characteristic of many roadside or fieldside finds that have gone unnoticed for generations. This particular rock was identified as rock art by George Currie in 2018, suggesting it had not previously entered the formal archaeological record despite sitting in plain sight beside a public road.