Clot, congeal (9)
I believe the answer is:
coagulate
I believe this is a double definition.
'clot' is the first definition.
(synonyms)
'congeal' is the second definition.
(I've seen this before)
(Other definitions for coagulate that I've seen before include "Set" , "Congeal" , "Cause to clot" , "(Of blood) solidify" , "Change from liquid into semi-solid as in catalogue" .)