n.
Function: adjective
Date: before 12th century
1 : of, relating to, or made of iron
2 : resembling iron
3 a : strong and healthy : ROBUST <an iron constitution> b : INFLEXIBLE , UNRELENTING < iron determination> c : holding or binding fast <an iron grip>
– iron · ness \ ' ī (- ə )rn-n ə s \ noun