If you have a hash which specifies an ordering for values, then your sorting is much easier:

my %hash = (
  "very slow"  => 1,
  "slow"       => 2,
  "slowish"    => 3,
  "medium"     => 4,
  "acceptable" => 5,
  "fast"       => 6,
  "very fast"  => 7,
);
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Now to sort, we just compare the array elements as keys into the hash:

my @sorted = sort { $hash{$a} <=> $hash{$b} } @array;
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Hence:

my @array = ("slow", "very fast", "fast", "very slow", "acceptable");
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would sort into:

very slow, slow, acceptable, fast, very fast
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