Ploidacot
The Ploidacot system is a classification of rank 2 temperaments based on pergen, i.e. how a temperament can be thought of as a union of copies of Pythagorean tuning.
Ploids
Any rank 2 temperament must split the octave into a number of ploids, for instance pajara divides the octave into two so it's diploid. Temperaments that don't divide the octave are called haploid.
Cots
If 3/2 is represented by a linearly independent element to the ploid, there is a number of ploids which when added to 3/2 gives the interval which splits into the largest number of parts by the temperament. Each of these parts is called a cot and the Ploidacot system uses a Greek letter to describe the smallest number of ploids should be added to 3/2 to form a whole number of cots, and this number of cots is indicated by a Greek numerical prefix.
Examples
pajara and injera are diploid augene is triploid diminished is tetraploid
mohajira is dicot semaphore is alpha-dicot slendric is tricot tricot is alpha-tricot porcupine is beta-tricot
tetracot is tetracot squares is beta-tetracot
bleu is pentacot magic is alpha-pentacot
miracle is hexacot hanson is alpha-hexacot
ennealimmal is enneaploid dicot