The information on the Historic Environment Viewer says this stone is 1.2m high × 0.7m wide × 0.6m thick, with a shallow depression on top. There's a quartz stone nearby too, 0.6m high × c. 0.7m × 0.6m. And "according to local tradition the standing stone was used as a Mass Rock". There's a story from the Schools Collection of the 1930s transcribed at duchas.ie:
It is a large stone standing upright with a large white stone to the Moville side.
One side of the stone has mouldered away with the storm.
The owner of the field was asked to remove the stone but he objected. He said his mother told him not to remove it for any quantity of gold or silver. The stone has been there for thousands of years and the story has been handed down from sire to son. It has been called from the beginning of time "the standing stone" or "the fairy grove."
It is about four feet high and two feet broad.
It is said that some of the older people who are not alive nowadays, saw a fairy appear, and this belief still holds good to the ones who owns the fields with the stone, which it contains, and they won't remove it.