Jess n. : A short strap of leather or silk secured round the leg of a hawk, to which the leash or line, wrapped round the falconer's hand, was attached when used. See Illust. of Falcon.

Example:
What season does Jess and Rory start dating?

Taxonomy
Jess, Rule Engine, the Rule, Java Platform, Ernest Friedman-Hill, Rete algorithm, Pattern, Java objects, Sandia National Laboratories, download, JavaTM, Boot Camp, Dallas, Ft. Worth, Jason Morris, two-day introduction, Sun's Java, Livermore, CA.

Defination from the web:
Jess is a rule engine and scripting environment written entirely in Sun's Java language by Ernest Friedman-Hill at Sandia National Laboratories in Livermore, CA. Using Jess, you can build Java software that has the capacity to "reason" using knowledge you supply in the form of declarative rules. ...