Stricter, starker or more serious (7)
I believe the answer is:
sterner
(Other definitions for sterner that I've seen before include "more inflexible anyway" , "More demanding" , "More severe" , "Less easy-going" , "More grimly serious" .)
I believe the answer is:
sterner
(Other definitions for sterner that I've seen before include "more inflexible anyway" , "More demanding" , "More severe" , "Less easy-going" , "More grimly serious" .)