... $findit .= "/\Q$term\E/i $param "; 

##</code><code>##

$findit_re = "\\b(?i:\Q$term\E)\\b";

##</code><code>##

$findit_re = qr/\b(?i:\Q$term\E)\b/;

##</code><code>##

my $target = "[a]";
if ($string =~ m/$target/) { ... }

##</code><code>##

my $target = "[a]";
if ($string =~ m/\Q$target\E/) { ... }
# or:
my $re = quotemeta($target);
if ($string =~ m/$re/) { ... }