Check this out.

# ps -aux | grep tail
root   19775  0.1  0.2  968  656 pts/3    S 17:07:27  0:00 grep tail
root    3030  0.0  0.2 1008  696 pts/4    S 10:23:21  0:00 tail -f /va
+r/adm/dd

# ps -aux | grep 't\ail'
root    3030  0.0  0.2 1008  696 pts/4    S 10:23:21  0:00 tail -f /va
+r/adm/dd
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Update: I like petral's way.

First time I saw this I thought it was a typo. ;) Pick a character that doesn't have special meaning to grep when '\' is used before it.

or
# ps -aux | grep '(httpd|named)' | grep -v grep
or
#!/usr/bin/perl
@ps = qx(ps aux);
@httpd = grep {/httpd/} @ps;
@named = grep {/named/} @ps;
print "httpd's:\n\t", join("\n\t", @httpd),
 "\nnamed's:\n\t", join("\n\t", @named), "\n";
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