Not in the same way as the equivelent in
Sindarin or
Quenya would be "
Elvish" or in
Westron would be "Manish". If "Lok'tar" is in "The
Black Speech" then it would be, "Mordorian", if it were not the Black Speech then it would be from a tribal speech that might not be understood by
Orcs from a tribe or group 10 miles away.
I think that my post was not as clear as it could have been. I did not mean that there is no such thing as "
Orcish" but that, with the exception of the Black Speech (invented and imposed by
Sauron), each tribe or group had their own speech which could not be understood even by other groups of Orcs.
This could be why Orcs only formed large offensive
armies when under the command of
Melkor or Sauron. At other times, although extremely dangerous they were only regional problems.