n.
Pronunciation: ' fas(t)-n ə s
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 >