Solid, firm, rigid (4)
I believe the answer is:
hard
(Other definitions for hard that I've seen before include "Intensely" , "Strenuous" , "Solid; tough" , "Emergency lane" , "badly" .)
I believe the answer is:
hard
(Other definitions for hard that I've seen before include "Intensely" , "Strenuous" , "Solid; tough" , "Emergency lane" , "badly" .)