Answer: epitope

AnswerCrossword Clue
epitopea part of an antigen complementary to an antibody
epitopedetermining agent or factor
epitopeany site on an antigen molecule at which an antibody can bind, the chemical structure of the site determining the specific combining antibody
epitopealgebraic expression of the sum of products of elements, each with an appropriate algebraic sign, usually written in a square array and used in the solution of systems of linear equations