1. A mathematical transform involving partial derivatives in college vector calculus courses.

2. The mortal enemies of the BasILL face that have alliances to Reimann Sums and Laplace Transforms. Syn: Porcelli.

3. Any person, thing, or situation that stops at nothing to slow you down, mess you up, or give you (or any BasILL) random unexpected grief.
"Yo man that 416 forecast was total Jacobian"
hahah I know man the Linux side was all messed up

OR

"Haha how'd you do on that Math230 exam?"
Yo man nothing but tru BasIll on that joint, the Jacobians didn't stand a chance
by Carl A. Jacobi April 11, 2006
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