| Nevertheless, the heterogram ZY does in fact occur in the Parthian inscriptions of the Arsacid period. |
| This is because there are only 5 different vowels available, so that any V-C pattern with more than 5 vowels is automatically ruled out of a heterogram exercise. |
| For example, the superconstraints in Alphabets affect the same material as the basic constraint of the heterogram, namely the eleven letters. |
| There is only one perfect heterogram, cab, plus its inferior anagrams, ABC and bac. |
| One heterogram seems to serve here for two different Iranian words of related meaning. |
| One has 14 letters, the other has 10 and is also the second longest heterogram. |
