Reconstruction:Proto-Slavic/tvьrdь

Etymology
From.

Noun

 * 1) citadel, firmament

Descendants

 * East Slavic:
 * South Slavic:
 * West Slavic:
 * South Slavic:
 * West Slavic:
 * West Slavic:
 * West Slavic:
 * West Slavic:
 * West Slavic: