Sorry, much late to the party, but I'll add here that if you wanted to capture processes with names identical to your search string, you could do
pgrep -x PROCESS_NAME
-x Require an exact match of the process name, or argument list if -f is given. The default is to match any substring.
This is extremely useful if your original process created child processes (possibly zombie when you query) which prefix the original process' name in their own name and you are trying to exclude them from your results. There are many UNIX daemons which do this. My go-to example is ninja-dev-sync.