Synonyms for Determinant (same or very similar meaning)
WordNet sense 1 (the site on the surface of an antigen molecule to which an antibody attaches itself):
antigenic determinant, epitope
WordNet sense 2 (a determining or causal element or factor):
determiner, determinative, causal factor, determining factor
WordNet sense 3 (having the power or quality of deciding):
crucial, deciding, determining
From the ODE community, based on WordNet
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