Nag n. : A small horse; a pony; hence, any horse.

Nag n. : A paramour; -- in contempt.

Nag v. t. & i. : To tease in a petty way; to scold habitually; to annoy; to fret pertinaciously.

Example:
Where can i buy Nag champa incense?

Taxonomy
Numerical Algorithms Group, research, Fortran 77, Fortran 90, science, engineering, software, math software, financial analysis, MATLAB, mathematical software, C Library, textware, f90, f95, statistical software components, numerical software, simulation software.

Defination from the web:
NAG produce and distribute numerical, symbolic, statistical, visualisation and simulation software for the solution of problems in such areas as science, engineering, financial analysis and research.