Selfsame is first described as late Middle English, an emphatic compound of 'self' (Old English 'self') + 'same' (from Old Norse 'samr', 'same'). The historical chain includes Old English self and Old Norse samr. Older glosses in the chain include "self", "same", and "samr", which help explain the semantic range of the modern word. Morphologically, selfsame is best read as compound and borrowing, yielding an English adjective shaped by both form history and later usage. In current English it functions as an adjective, with the sense "exactly the same; identical". English derivatives include selfsameness; related forms include self and same. The result is an English adjective whose etymology preserves the older forms while supporting the word's specialized modern meaning.