determinant

from The American Heritage® Dictionary of the English Language, 5th Edition.

• adjective Determinative.
• noun An influencing or determining element or factor.
• noun Mathematics The value computed from a square matrix of numbers by a rule of combining products of the matrix entries and that characterizes the solvablitity of simultaneous linear equations. Its absolute value can be interpreted as an area or volume.
• noun Immunology An epitope.

from The Century Dictionary.

• noun In biology, in Weismann's doctrine of germ-plasm, the material bearer of all the hereditary qualities of a cell, regarded as composed of as many biophores, or bearers of single hereditary qualities, as are to be possessed by the cell and its descendants.
• Serving to determine; determinative.
• noun That which determines, fixes, defines, or establishes something.
• noun In old universities, one who, having taken the lowest degree in arts, had been admitted to act as chief respondent in the Lenten disputations.
• noun In mathematics, the sum of all the products which can be formed of a square block of quantities, each product containing as a factor one number from each row and one from each column of the block, and each product being affected by the plus or minus sign according as the arrangement of rows from which its factors are taken (these factors being arranged in the order of the columns from which they are taken) requires an even or an odd number of transpositions to reduce it to the arrangement in the square.
• noun of the r order, a function of r constituents, analogous to an ordinary determinant.

from the GNU version of the Collaborative International Dictionary of English.

• adjective Serving to determine or limit; determinative.
• noun That which serves to determine; that which causes determination.
• noun (Math.) The sum of a series of products of several numbers, these products being formed according to certain specified laws.
• noun (Logic) A mark or attribute, attached to the subject or predicate, narrowing the extent of both, but rendering them more definite and precise.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A determining factor; an element that determines the nature of something
• noun linear algebra The unique scalar function over square matrices which is distributive over matrix multiplication, multilinear in the rows and columns, and takes the value of 1 for the unit matrix. Abbreviation: det
• noun biology A substance that causes a cell to adopt a particular fate.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun the site on the surface of an antigen molecule to which an antibody attaches itself
• noun a determining or causal element or factor
• noun a square matrix used to solve simultaneous equations
• adjective having the power or quality of deciding