determinant

Short definition from Wiktionary

Noun

1. 1
   A determining factor; an element that determines the nature of something.
2. 2
   A scalar that encodes certain characteristics of a given transformation matrix; the unique scalar function over square matrices which is distributive over matrix multiplication, multilinear in the rows and columns, and takes the value 1 for the unit matrix; abbreviated as: det.
3. 3
   A substance that causes a cell to adopt a particular fate.
4. 4
   Something that causes a nuclease to cut at a specified point

Adjective

1. 1
   Serving to determine or limit; determinative.