How do I change the path that is being searched for launching an application?

I am trying to launch the D programming language compiler DMD, but the terminal is giving the following error:

dmd: failed to launch executable at /Library/Compilers/dmd2/osx/bin/dmd

But there's not folder called dmd2 under /Library/Compilers.

I can launch the dmd compiler from this path /usr/bin/dmd, but I don't want to type this path every time I need to compile a source code file.

This is my $PATH:

/Library/Frameworks/Python.framework/Versions/2.7/bin:/Library/Frameworks/Python.framework/Versions/3.4/bin:/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin:/opt/X11/bin:/usr/texbin

Is there a way that when I type dmd it launches /usr/bin/dmd, instead of trying to language a compiler under /Library/Compilers/dmd2/osx/bin/dmd?