From The Free On-line Dictionary of Computing: (http://www.foldoc.org/, Editor Denis Howe)
The GNUCompiler Collection, which currently contains front ends for C, C++, Objective-C, Fortran, Java, and Ada, as well as libraries for these languages (libstdc++, libgcj, etc).
GCC formerly meant the GNU C compiler, which is a very high quality, very portable compiler for C, C++ and Objective C.