alligation
noun
al·li·ga·tion
| \ ˌal-ə-ˈgā-shən
\
\
Medical Definition of alligation
: a process or rule for the solution of problems concerning the compounding or mixing of ingredients differing in price or quality:
a
: one applied when a definite mixture is required
— called also alligation alternate
b
: one applied when the price or quality of the mixture is to be determined
— called also alligation medial