Translation according to P. W. Joyce:
Cushatrough in Galway ; Cois-a'-tsrotha [-trogha], along the sruih [sruh], or stream. S eclipsed by t. See Sruth, vol. i. p. 457.
Sruth [sruh] means a stream, and it is in very common use both in the spoken and written language. It is an ancient and primitive word in Irish, being found in the Wb. MS. Of Zeuss, where it glosses flumen, rivus; it is almost identical with Sansc. Sróta, a river; and its cognates exist in several other languages, such as Welsh frut, Cornish frot, Slavonic struja, Old High German stroum, Eng. stream (Ebel). Sruth occurs pretty often in names, and its various derivatives, especially the diminutives, have also impressed themselves extensively on the nomenclature of the country. In its simple form it gives names to Srue in Galway; to Shruh in Waterford; and to Shrough in Tipperary; Ballystrew near Downpatrick is the town of the stream.