Medical Definition of alpha
1: of or relating to one of two or more closely related chemical substances <the alpha chain of hemoglobin> <α-yohimbine>—used somewhat arbitrarily to specify ordinal relationship or a particular physical form, especially one that is allotropic, isomeric, stereoisomeric, or sometimes polymeric (as in α-D-glucose)
2: closest in position in the structure of an organic molecule to a particular group or atom; also : occurring at or having a structure characterized by such a position <α-substitution>
Variants of alpha
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