Looks like this was created either by mistake by a user or by a program with a bug in it (I'd guess some SQL script which uses variable expansion with the '&variablename' syntax that SQL*PLUS uses, but the expansion didn't happen for some reason).
Anyhow, to the shell, the & character is a special one which tells the shell to put the command which comes before it into the background (using shell job control).
You can tell the shell not to interpret the & character in this way by quoting your argument to cd (or whatever command you are trying to execute):