Main Entry: fast·ness

Pronunciation: \ˈfas(t)-nəs\

Function: noun

Date: before 12th century

1 : the quality or state of being fast: as a : the quality or state of being fixed b : the quality or state of being swift c : colorfast quality d : resistance (as of an organism) to the action of a usually toxic substance
2 a : a fortified or secure place b : a remote and secluded place <vacationed in their mountain fastness>