What the parser considers a bareword does depend on what it's seen tho.

use warnings;
use strict;
BEGIN { $INC{'Blah.pm'}=1 }
sub Blah::import { print "@_\n" }
sub abc { 42 }
use Blah -abc; # "Blah -42"
use Blah -def; # *still* "Blah -def"
sub def { 999 }
[download]

Barewords: "A word that has no other interpretation in the grammar will be treated as if it were a quoted string. ... use strict 'subs'; then any bareword that would NOT be interpreted as a subroutine call produces a compile-time error instead."