Sia is a dialectal northern English and Scots variant spelling of say, from Old English secgan ('to say, speak'), from Proto-Germanic *sagjaną. The historical chain includes Old English secgan and Proto-Germanic *sagjaną. Older glosses in the chain include "to say, speak", which help explain the semantic range of the modern word. Morphologically, sia is best read as borrowing, yielding an English noun shaped by both form history and later usage. In current English it functions as a noun, with the sense "a dialectal or archaic spelling of "say" used in northern English speech". related forms include say. The result is an English noun whose etymology preserves the older forms while supporting the word's specialized modern meaning.