spegelblank
Spegelblank is a compound adjective in Swedish and related Scandinavian languages, formed from spegel (mirror) and blank (shiny, bright). It describes a surface that is exceptionally smooth and reflective, producing clear mirror-like reflections. The term is most commonly applied to bodies of water—lakes, fjords or seas—when wind and waves are absent and the water surface appears glassy.
In grammatical use, spegelblank agrees with the noun it modifies; for example, spegelblankt is the neuter form
Etymologically, both elements are of Germanic origin and reflect a straightforward descriptive tradition in Scandinavian compound